Allow executing CREATE statement multiple times

patch by slebresne; reviewed by jbellis for CASSANDRA-6471
Don't send confusing info on timeouts

patch by slebresne; reviewed by jbellis for CASSANDRA-6491
Don't drop local mutations without a trace

patch by Aleksey Yeschenko; reviewed by Jonathan Ellis for
CASSANDRA-6510
Don't allow null max_hint_window_in_ms
patch by Nate McCall; reviewed by jbellis for CASSANDRA-6419
Fix typo
OCD follow up
Validate SliceRange start and finish lengths

patch by Ben Bromhead; reviewed by Aleksey Yeschenko for CASSANDRA-6521
add .gitignore
patch by Michael Shuler; reviewed by jbellis for CASSANDRA-4899
fsync compression metadata
patch by jbellis; reviewed by Pavel Yaskevich for CASSANDRA-6531
shutdown() the compaction strategy in CFS.invalidate()
make CM.Writer.close idempotent
Allow nodetool to optionally resolve hostnames.
Patch by Daneel S. Yaitskov, reviewed by brandonwilliams for
CASSANDRA-2238
Validate CF existence on execution for prepared statement

patch by aholmber; reviewed by slebresne for CASSANDRA-6535
Add ability to throttle batchlog replay

patch by Aleksey Yeschenko; reviewed by Jonathan Ellis for
CASSANDRA-6550