Merge branch 'cassandra-1.2' into cassandra-2.0
merge from 1.2
Merge branch 'cassandra-2.0' into trunk
Fix thrift validation refusing row markers on CQL3 tables

patch by slebresne; reviewed by jbellis for CASSANDRA-6081
Fix insertion of collections with CAS

patch by slebresne; reviewed by iamaleksey for CASSANDRA-6069
Merge branch 'cassandra-2.0' into trunk
Add tombstone debug threshold and histogram
patch by Russell Spitzer and Lyuben Todorov; reviewed by jbellis for CASSANDRA-6042 and CASSANDRA-6057
merge from 1.2
Merge branch 'cassandra-2.0' into trunk
fix CHANGES
Merge branch 'cassandra-1.2' into cassandra-2.0
merge from 1.2
Merge branch 'cassandra-2.0' into trunk
Enable tcp keepalive on incoming connections.

Patch by marcuse, reviewed by jbellis for CASSANDRA-4053
Merge branch 'cassandra-2.0' into trunk
add snapshot repair to NodeToolHelp.yaml
Merge branch 'cassandra-1.2' into cassandra-2.0
Merge branch 'cassandra-2.0' into trunk
Send correct metadata on SELECT COUNT

patch by slebresne; reviewed by iamaleksey for CASSANDRA-6080
Merge branch 'cassandra-2.0' into trunk