Use Hive instance to do ddl to metastore

 Access partition list in a synchronized manner
fix test by clearing the inmemory maps
use treeset instead of arraylist to keep partitions which needs to eb registered
remove hcatclient related code from conduit.java file
Refactor service constructors: remove hcatutil parameter
use hive instance for creating and accessing partitions
use hive instance for dropping the partitions
Change the logic in finding the date from partition
instantiate hive with specified hiveconf
pass db name aswell to the methods which access metastore
fix tests: remove hcatutil instance from all the tests
close the connections to metastore when user issues a stop
test changes
get the partitions for dropping which matches the partspec and drop partitions one by one
create db, tables and partitions using hive instance in test hcat util
add a test calss for testing the databus-hcat related methods
Refactor code and check the status of dropping the partitions in purger service
remove hcatclient related from TestHCatUtil and fix NPE in conduit
remove hcat dependencies from pom
remove a test class which is not required and remove unused imports
remove hcatutil.java from src and remove partition value list from partition desc in datapurger service
change the comparator logic and ge the table name for stream once instead of querying everytime and fix tests cases
fix review comments