HIVE-2598. Update README.txt file to use description from wiki

(Carl Steinbach via jvs)



git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1203885 13f79535-47bb-0310-9956-ffa450edef68

README.txt

@@ -1,14 +1,27 @@
-Apache Hive @VERSION@
-=================
-
-Apache Hive is a data warehouse system for Hadoop that facilitates
-easy data summarization, ad-hoc querying and analysis of large
-datasets stored in Hadoop compatible file systems. Hive provides a
-mechanism to put structure on this data and query the data using a
-SQL-like language called HiveQL. At the same time this language also
-allows traditional map/reduce programmers to plug in their custom
-mappers and reducers when it is inconvenient or inefficient to express
-this logic in HiveQL.
+Apache Hive (TM) @VERSION@
+======================
+
+The Apache Hive (TM) data warehouse software facilitates querying and
+managing large datasets residing in distributed storage. Built on top
+of Apache Hadoop (TM), it provides:
+
+* Tools to enable easy data extract/transform/load (ETL)
+
+* A mechanism to impose structure on a variety of data formats
+
+* Access to files stored either directly in Apache HDFS (TM) or in other
+  data storage systems such as Apache HBase (TM)
+
+* Query execution via MapReduce
+
+Hive defines a simple SQL-like query language, called QL, that enables
+users familiar with SQL to query the data. At the same time, this
+language also allows programmers who are familiar with the MapReduce
+framework to be able to plug in their custom mappers and reducers to
+perform more sophisticated analysis that may not be supported by the
+built-in capabilities of the language. QL can also be extended with
+custom scalar functions (UDF's), aggregations (UDAF's), and table
+functions (UDTF's).
 
 Please note that Hadoop is a batch processing system and Hadoop jobs
 tend to have high latency and incur substantial overheads in job