Provide hooks around CQL2/CQL3 statement execution

patch by Sam Tunnicliffe; reviewed by Aleksey Yeschenko for
CASSANDRA-6252
Require Permission.SELECT for CAS updates

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-6247
Require logging in for Thrift CQL2/3 statement preparation

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-6254
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	CHANGES.txt
	src/java/org/apache/cassandra/thrift/CassandraServer.java
Allow overriding max hin ttl.
Patch by Vishy Kasar, reviewed by brandonwilliams for CASSANDRA-5988
Merge branch 'cassandra-1.2' into cassandra-2.0
Allow overriding max hint ttl
Patch by Vishy Kasar and brandonwilliams, reviewed by brandonwilliams
for CASSANDRA-5988
Ninja: use v1 (time) instead of v4 (random) UUID for the batchlog
Show the root cause when failing to load a class
Patch by Jackson Chung, reviewed by brandonwilliams for CASSANDRA-6258
Merge branch 'cassandra-1.2' into cassandra-2.0
Fix native protocol spec v2
Add CQL-aware SSTableWriter

patch by slebresne; reviewed by jbellis for CASSANDRA-5894
Add beforeChange notification to IEndpointStateChangeSubscriber
Patch by Sergio Bossa, reviewed by brandonwilliams for CASSANDRA-6135
Compact hottest sstables first and optionally omit coldest
patch by Tyler Hobbs; reviewed by jbellis for CASSANDRA-6109
add generation back to bucketing (filtering) sort
update COLD_READS_TO_OMIT_KEY
Remove CHANGES.txt dups
Make MS.getBoundTerms() correct for batched statements

patch by Aleksey Yeschenko and Sam Tunnicliffe; reviewed by
Sylvain Lebresne
Fixes for compacting larger-than-memory rows
patch by jbellis; reviewed by marcuse for CASSANDRA-6274
restrict max_num_tokens to 1536
patch by jbellis; reviewed by brandonwilliams and Quentin Conner for CASSANDRA-6267