[#77] [Standalone] Exporting GIMEL_HOME by default

### GitHub Issue
Fixes #77


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docs/try-gimel/0-prerequisite.md

@@ -56,12 +56,6 @@ ________________________________________________________________________________
 ```
 cd gimel
 ```
-
-* Export GIMEL_HOME variable by setting it to the current folder.
-```
-export GIMEL_HOME=`pwd`
-echo $GIMEL_HOME
-```
 * Navigate to the folder gimel-dataapi/gimel-standalone/ - ```cd gimel-dataapi/gimel-standalone/```
 * Create lib folder in gimel-standalone - ```mkdir lib```
 * Copy the downloaded jar in lib

quickstart/set-env

@@ -23,5 +23,3 @@ export standalone_dir=${gimel_repo_home}/gimel-dataapi/gimel-standalone
 export gimel_jar_name=gimel-sql-1.2.0-SNAPSHOT-uber.jar
 export final_jar=${standalone_dir}/lib/$gimel_jar_name
 export FLIGHTS_DATA_PATH=$GIMEL_HOME/gimel-dataapi/gimel-quickstart/flights
-
-

quickstart/start-gimel

@@ -15,11 +15,17 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-export this_dir=`dirname $0`
-source $this_dir/set-env
+export this_file=${0}
+export this_script_path="$( cd "$( dirname "$this_file" )" && pwd)"
+cd ${this_script_path}
+cd ..
+export GIMEL_HOME=${PWD}
 source ${GIMEL_HOME}/build/gimel_functions
+write_log "Current Working Directory is  ${GIMEL_HOME}"
+export this_dir=`dirname $0`
+source ${this_script_path}/set-env
 
-write_log "Stop if any container is running already..."
+write_log "Stop if any container is running already"
 run_cmd "sh $GIMEL_HOME/quickstart/stop-gimel stop"
 
 mkdir ${GIMEL_HOME}/tmp ${GIMEL_HOME}/lib