[ZEPPELIN-1489] Remove jdbc-like interpreter example properties and i…

…mprove JDBC docs

### What is this PR for?
Currently we can use `%jdbc(prefix)` for multi database connections(e.g. configuring both postgresql and hive in one JDBC interpreter). But after #1360 merged, Zeppelin doesn't support `%jdbc(prefix)` to `%prefix` anymore. So auto-prefix feature is not working for `%jdbc(prefix)`. The auto-prefix only works for `%prefix` now. Considering this status, it would be better we remove the JDBC connection examples in `jdbc/interpreter-setting.json` (this is come from #1096) so that users can create several JDBC interpreters instead of using multiple connections with one JDBC interpreter.  I removed the related contents in `jdbc.md` as well.

Also, the contents of [current JDBC documentation page](http://zeppelin.apache.org/docs/0.7.0-SNAPSHOT/interpreter/jdbc.html) is quite confusing and unorganized. So I updated the contents with some screenshot images to guide "How to create JDBC interpreter", "How to edit the interpreter properties for the connection", "How to use `%prefix` with the interpreter", and so on.

### What type of PR is it?
Improvement & Documentation

### What is the Jira issue?
[ZEPPELIN-1489](https://issues.apache.org/jira/browse/ZEPPELIN-1489)

### How should this be tested?
* Removing example properties in `interpreter-setting.json`
  1. after applying this patch and build with `mvn clean package -DskipTests -Pspark-1.6 -pl 'jdbc,zeppelin-interpreter,zeppelin-web,zeppelin-server,zeppelin-zengine,zeppelin-display'`
  2. create JDBC interpreter and check whether the example settings are gone or not

* JDBC docs
  1. Build only `docs/` dir as described in [here](https://github.com/apache/zeppelin/blob/master/docs/README.md#build-documentation)
  2. Go to `interpreter -> JDBC` and just compare this locally builded page with [the original JDBC page](https://zeppelin.apache.org/docs/0.7.0-SNAPSHOT/interpreter/jdbc.html)

### Screenshots (if appropriate)
 - Before
<img width="1579" alt="before" src="https://cloud.githubusercontent.com/assets/10060731/19045323/1ff0c706-89d3-11e6-9b6f-dc75877f81f3.png">

 - After
<img width="944" alt="screen shot 2016-10-04 at 1 05 00 am" src="https://cloud.githubusercontent.com/assets/10060731/19045324/24a9187a-89d3-11e6-90d6-b80acbc6af7c.png">

 - Some parts of updated JDBC docs
Since many contents are changed, it would be better to build `docs/` locally to review all of the change.

<img width="695" alt="screen shot 2016-10-04 at 12 36 39 am" src="https://cloud.githubusercontent.com/assets/10060731/19043794/9d9a32fc-89cc-11e6-9d15-f6036a1b738e.png">

<img width="704" alt="screen shot 2016-10-04 at 12 36 59 am" src="https://cloud.githubusercontent.com/assets/10060731/19043800/a62fc90e-89cc-11e6-976d-5c697729eca4.png">

<img width="677" alt="screen shot 2016-10-04 at 12 37 31 am" src="https://cloud.githubusercontent.com/assets/10060731/19043807/acbc9766-89cc-11e6-8c73-eab1cc18440b.png">

<img width="688" alt="screen shot 2016-10-04 at 12 37 43 am" src="https://cloud.githubusercontent.com/assets/10060731/19043816/b06b5690-89cc-11e6-9298-a20b49fea622.png">

### Questions:
* Does the licenses files need update? no
* Is there breaking changes for older versions? no
* Does this needs documentation? yes

Author: AhyoungRyu <ahyoungryu@apache.org>

Closes #1480 from AhyoungRyu/ZEPPELIN-1489 and squashes the following commits:

76bf55e [AhyoungRyu] Minor update
d5aaa97 [AhyoungRyu] Remove useless screenshot images
c6f9ed4 [AhyoungRyu] Add screenshot images
99a18e2 [AhyoungRyu] Remove jdbc setting examples in interpreter-setting.json
050ecc0 [AhyoungRyu] Update jdbc.md
20da102 [AhyoungRyu] Redshit -> Redshift in JDBCInterpreter.java

jdbc/src/main/java/org/apache/zeppelin/jdbc/JDBCInterpreter.java

@@ -49,7 +49,7 @@
 
 /**
  * JDBC interpreter for Zeppelin. This interpreter can also be used for accessing HAWQ,
- * GreenplumDB, MariaDB, MySQL, Postgres and Redshit.
+ * GreenplumDB, MariaDB, MySQL, Postgres and Redshift.
  *
  * <ul>
  * <li>{@code default.url} - JDBC URL to connect to.</li>

jdbc/src/main/resources/interpreter-setting.json

@@ -63,96 +63,6 @@
         "propertyName": "zeppelin.jdbc.principal",
         "defaultValue": "",
         "description": "Kerberos principal"
-      },
-      "hive.url": {
-        "envName": null,
-        "propertyName": "hive.url",
-        "defaultValue": "jdbc:hive2://localhost:10000",
-        "description": ""
-      },
-      "hive.user": {
-        "envName": null,
-        "propertyName": "hive.user",
-        "defaultValue": "hive",
-        "description": ""
-      },
-      "hive.password": {
-        "envName": null,
-        "propertyName": "hive.password",
-        "defaultValue": "",
-        "description": ""
-      },
-      "hive.driver": {
-        "envName": null,
-        "propertyName": "hive.driver",
-        "defaultValue": "org.apache.hive.jdbc.HiveDriver",
-        "description": ""
-      },
-      "phoenix.url": {
-        "envName": null,
-        "propertyName": "phoenix.url",
-        "defaultValue": "jdbc:phoenix:localhost:2181:/hbase-unsecure",
-        "description": ""
-      },
-      "phoenix.user": {
-        "envName": null,
-        "propertyName": "phoenix.user",
-        "defaultValue": "phoenixuser",
-        "description": ""
-      },
-      "phoenix.password": {
-        "envName": null,
-        "propertyName": "phoenix.password",
-        "defaultValue": "",
-        "description": ""
-      },
-      "phoenix.driver": {
-        "envName": null,
-        "propertyName": "phoenix.driver",
-        "defaultValue": "org.apache.phoenix.jdbc.PhoenixDriver",
-        "description": ""
-      },
-      "phoenix.hbase.client.retries.number": {
-        "envName": null,
-        "propertyName": "phoenix.hbase.client.retries.number",
-        "defaultValue": "1",
-        "description": "Maximum retries.  Used as maximum for all retryable operations such as the getting of a cell's value, starting a row update, etc."
-      },
-      "tajo.url": {
-        "envName": null,
-        "propertyName": "tajo.url",
-        "defaultValue": "jdbc:tajo://localhost:26002/default",
-        "description": ""
-      },
-      "tajo.driver": {
-        "envName": null,
-        "propertyName": "tajo.driver",
-        "defaultValue": "org.apache.tajo.jdbc.TajoDriver",
-        "description": ""
-      },
-      "psql.url": {
-        "envName": null,
-        "propertyName": "psql.url",
-        "defaultValue": "jdbc:postgresql://localhost:5432/",
-        "description": ""
-      },
-      "psql.user": {
-        "envName": null,
-        "propertyName": "psql.user",
-        "defaultValue": "phoenixuser",
-        "description": ""
-      },
-      "psql.password": {
-        "envName": null,
-        "propertyName": "psql.password",
-        "defaultValue": "",
-        "description": ""
-      },
-      "psql.driver": {
-        "envName": null,
-        "propertyName": "psql.driver",
-        "defaultValue": "org.postgresql.Driver",
-        "description": ""
       }
     },
     "editor": {