Catch memtable flush exceptions during shutdown
patch by Sergio Bossa; reviewed by jbellis for CASSANDRA-6735
merge from 1.2
Merge branch 'cassandra-2.0' into cassandra-2.1
Return an empty meta object instead of None.
Patch by Mikhail Stepura; reviewed by Brandon Williams for CASSANDRA-6741
Fix AIOOBE when concurrently accessing ABSC

patch by Aleksey Yeschenko and Benedict Elliott Smith for CASSANDRA-6742
CASSANDRA-6742 follow up
Adjust nodetool for changes from CASSANDRA-5549.
patch by Mikhail Stepura; reviewed by Yuki Morishita for CASSANDRA-6739
r/m unused HeaderTypes class (CASSANDRA-6743)
Merge branch 'cassandra-2.0' into cassandra-2.1
Add static columns in CQL3

patch by slebresne; reviewed by iamaleksey for CASSANDRA-6561
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	src/java/org/apache/cassandra/config/CFMetaData.java
	src/java/org/apache/cassandra/config/ColumnDefinition.java
	src/java/org/apache/cassandra/cql3/CFDefinition.java
	src/java/org/apache/cassandra/cql3/Constants.java
	src/java/org/apache/cassandra/cql3/Cql.g
	src/java/org/apache/cassandra/cql3/Lists.java
	src/java/org/apache/cassandra/cql3/Maps.java
	src/java/org/apache/cassandra/cql3/Operation.java
	src/java/org/apache/cassandra/cql3/Sets.java
	src/java/org/apache/cassandra/cql3/functions/TokenFct.java
	src/java/org/apache/cassandra/cql3/statements/AlterTableStatement.java
	src/java/org/apache/cassandra/cql3/statements/BatchStatement.java
	src/java/org/apache/cassandra/cql3/statements/ColumnGroupMap.java
	src/java/org/apache/cassandra/cql3/statements/CreateIndexStatement.java
	src/java/org/apache/cassandra/cql3/statements/CreateTableStatement.java
	src/java/org/apache/cassandra/cql3/statements/DeleteStatement.java
	src/java/org/apache/cassandra/cql3/statements/ModificationStatement.java
	src/java/org/apache/cassandra/cql3/statements/SelectStatement.java
	src/java/org/apache/cassandra/cql3/statements/Selection.java
	src/java/org/apache/cassandra/cql3/statements/UpdateStatement.java
	src/java/org/apache/cassandra/db/filter/ColumnSlice.java
	src/java/org/apache/cassandra/db/index/composites/CompositesSearcher.java
	src/java/org/apache/cassandra/hadoop/pig/AbstractCassandraStorage.java
	src/java/org/apache/cassandra/hadoop/pig/CqlStorage.java
	src/java/org/apache/cassandra/thrift/ThriftValidation.java
Fix ABTC NPE
patch by Benedict Elliott Smith; reviewed by jbellis for CASSANDRA-6692
Better solution for CASSANDRA-6742

patch by Aleksey Yeschenko; reviewed by Benedict Elliott Smith for
CASSANDRA-6742
Fast ABSC.addAll() path + ASPCSI optimization

patch by Benedict Elliott Smith; reviewed by Aleksey Yeschenko
Post-merge fixup
Merge branch 'cassandra-2.1' of https://git-wip-us.apache.org/repos/asf/cassandra into cassandra-2.1
Fix typos
Merge branch 'cassandra-2.0' into cassandra-2.1
Optimize single partition batch statements

patch by slebresne; reviewed by benedict for CASSANDRA-6737
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	src/java/org/apache/cassandra/cql3/statements/BatchStatement.java
	src/java/org/apache/cassandra/cql3/statements/DeleteStatement.java
	src/java/org/apache/cassandra/cql3/statements/ModificationStatement.java
	src/java/org/apache/cassandra/cql3/statements/UpdateStatement.java
	src/java/org/apache/cassandra/db/Mutation.java