reduce logging statement overhead in removing record batch
DRILL-887: TestQueriesOnLargeFile.testMergingReceiver fails on Windows
Enable View persistence, Storage Plugin and System option persistence.

Conflicts:
	exec/java-exec/src/main/java/org/apache/drill/exec/ExecConstants.java
	exec/java-exec/src/test/java/org/apache/drill/exec/cache/TestCacheSerialization.java
Adding HBase Persistent Store.

+ Modified some interfaces and configuration keys.

Conflicts:
	exec/java-exec/src/main/java/org/apache/drill/exec/ExecConstants.java
Delete views after test and close ResultSet objects after use
Enable editing of storage plugin via http
DRILL-909: TestSimpleExternalSort.outOfMemoryExternalSort() hangs with use of UnlimitedRawBatchBuffer

- *Not a fix*. Disabling the failing test until a fix is checked in.
Add Web UIs using templates.

* Added GUI to storage.
* Query submission and sorted results.
Drill configuration changes

+ Moved bootstrap-storage-plugins.json from "conf/" to "java-exec" jar.
+ Cleared drill-override.conf and added drill-override-example.conf
+ Updated maven assembly descriptor.
Disable store persistence for unit tests.
Log Drillbit environment at start up.
Use PStore for profiles, partial profiles on running queries

Full profiles through rpc layer
DRILL-925: fix issues with dynamic memory allocation
add servlets to expose server level metrics.
Added 'extlib' folder which will contain 3rd party jars which override jars from other (Hadoop, HBase) projects.
Do not uppercase storage plugin configuration names.
Curator needs to be started before ServiceCache can be built.
DRILL-865: Interface changes to AbstractRecordBatch to enable easy collection of stats.
Add BaseRootExec as a wrapper to collect stats for senders.
Add BaseRootExec which will enable collection of stats for Senders
Add SenderStats that collects stats specific to senders.
DRILL-760: Move information schema to use POJO record reader