ACCUMULO-1691 Support Thrift 0.9.1

  Enforce version 0.9.1 until THRIFT-2173 is implemented, and provide a custom
  server so we can access the underlying transport to get the client address.
ACCUMULO-2773 Regenerate sources for Thrift 0.9.1
Merge branch '1.6.1-SNAPSHOT'

Conflicts:
	core/src/main/java/org/apache/accumulo/core/data/thrift/MultiScanResult.java
	core/src/main/java/org/apache/accumulo/core/data/thrift/ScanResult.java
	core/src/main/java/org/apache/accumulo/core/data/thrift/TConditionalMutation.java
	core/src/main/java/org/apache/accumulo/core/data/thrift/TMutation.java
	core/src/main/java/org/apache/accumulo/core/data/thrift/UpdateErrors.java
	server/base/src/main/java/org/apache/accumulo/server/util/TServerUtils.java
ACCUMULO-2789 Remove javadoc tag with no description
ACCUMULO-2905 Remove unused constant
Merge branch '1.5.2-SNAPSHOT' into 1.6.1-SNAPSHOT
ACCUMULO-2825 Remove javadoc tags without descriptions
ACCUMULO-2212 Remove unused imports
ACCUMULO-2383 Remove unused imports/variables
ACCUMULO-2343 Clean up unused imports/use of deprecated constants
ACCUMULO-2386 Fix use of generics
ACCUMULO-2887 Remove unused imports/variables
ACCUMULO-2791 Remove unused imports
ACCUMULO-2876 Remove unused import
ACCUMULO-2770 Properly suppress deprecation warnings
Merge branch '1.6.1-SNAPSHOT'

Conflicts:
	core/src/main/java/org/apache/accumulo/core/conf/ObservableConfiguration.java
	core/src/test/java/org/apache/accumulo/core/util/AsyncSocketAppenderTest.java
	server/base/src/main/java/org/apache/accumulo/server/zookeeper/ZooReaderWriterFactory.java
	server/tserver/src/main/java/org/apache/accumulo/tserver/log/LocalWALRecovery.java
ACCUMULO-378 Remove improper javadocs (no descriptions with tags)