Fix CleanupTest

patch by marcuse, reviewed by jbellis for CASSANDRA-6679
Log USING TTL/TIMESTAMP in a counter update warning

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-6649
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	src/java/org/apache/cassandra/cql3/statements/ModificationStatement.java
	test/unit/org/apache/cassandra/db/CleanupTest.java
Sleep for RING_DELAY before replacing with same IP
Patch by brandonwilliams reviewed by Tyler Hobbs for CASSANDRA-6622
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	CHANGES.txt
Sleep for RING_DELAY before replacing with same IP
Patch by brandonwilliams reviewed by Tyler Hobbs for CASSANDRA-6622
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	CHANGES.txt
Don't exchange schema between nodes with different versions

patch by Aleksey Yeschenko; reviewed by Piotr Kołaczkowski for
CASSANDRA-6695
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	src/java/org/apache/cassandra/service/MigrationManager.java
log at info when gossip is fine or people think it's still waiting
SS logging 'now serving reads' is misleading
only waitForGossip if we're configured for a multinode cluster
turns out there's already a getLoopbackAddress
remove dead code
Avoid overlaps in LCS by not skipping levels and verifying that the candidates
don't overlap any compacting sstables.

Patch by marcuse, reviewed by jbellis for CASSANDRA-6688
Use real node messaging versions for schema exchange decisions

patch by Aleksey Yeschenko; reviewed by Piotr Kołaczkowski for
CASSANDRA-6700
Merge branch 'cassandra-1.2' into cassandra-2.0
IN on the last clustering columns + ORDER BY DESC yield no results

patch by slebresne; reviewed by thobbs for CASSANDRA-6701
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	src/java/org/apache/cassandra/cql3/statements/SelectStatement.java
Fix SecondaryIndexManager#deleteFromIndexes()

patch by Sergio Bossa; reviewed by Sam Tunnicliffe for CASSANDRA-6711