Remove dead code

patch by slebresne; reviewed by jbellis for CASSANDRA-6580
Use LOCAL_QUORUM for LWT operations at LOCAL_SERIAL
patch by Sankalp Kohli; reviewed by jbellis for CASSANDRA-6495
Remove time penalty from DES.
Patch by Tyler Hobbs, reviewed by brandonwilliams for CASSANDRA-6465
Don't shutdown a nonexistant native server on 1.2, either.
Merge branch 'cassandra-1.2' into cassandra-2.0
Add LOCAL_SERIAL to ThriftConversion
Patch by brandonwilliams for CASSANDRA-6584
update changes
Refuse snapshots during bootstrap.
Patch by brandonwilliams, reviewed by thobbs for CASSANDRA-6585
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	src/java/org/apache/cassandra/service/StorageService.java
Avoid special casing received/expected counts in CAS timeout exceptions

patch by slebresne; reviewed by jbellis for CASSANDRA-6595
Add support for 2.1 global counter shards

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-6505
getValidColumnFamilies adds 2I if requested and no ks/cf specified
Patch by brandonwilliams, reviewed by jbellis for CASSANDRA-6598
getValidColumnFamilies adds 2I if requested and no ks/cf specified
Patch by brandonwilliams, reviewed by jbellis for CASSANDRA-6598
Add ks.cf names to tombstone logging
patch by Kevin Lovato; reviewed by jbellis for CASSANDRA-6597
Update NEWS for 6589
update CHANGES
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	src/java/org/apache/cassandra/service/StorageService.java
Check that key_aliases/column_aliases exists before using them
Patch by brandonwilliams, reviewed by iamaleksey for CASSANDRA-6589
fix indentation
HSHA rethrows OOM
Patch by Mikhail Stepura, reviewed by brandonwilliams for CASSANDRA-6255