Write row markers when serializing schema

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-5572
Merge branch 'cassandra-1.2' into trunk

Conflicts:
	CHANGES.txt
	src/java/org/apache/cassandra/config/CFMetaData.java
Check only SSTables for the requested range when streaming patch by Rick Branson; reviewed by yukim for CASSANDRA-5569
Merge branch 'cassandra-1.2' into trunk

Conflicts:
	src/java/org/apache/cassandra/db/ColumnFamilyStore.java
inline maxChange
move QF.isRelevant into CF.addIfRelevant
update NEWS for JEMalloc
remove unused imports
Cassandra Triggers!
patch by Vijay; reviewed by Jonathan Ellis for CASSANDRA-1311
don't declare throwing exceptions that aren't thrown
Replace ArrayBlockingQuery by LinkedBlockingQueue in binary protocol RequestThreadPoolExecutor
update CHANGES, NEWS for triggers
Avoid unnecessary second pass on name-based queries
patch by jbellis; reviewed by slebresne for CASSANDRA-5577
snappy-java upgrade to 1.0.5
Merge branch 'cassandra-1.2' into trunk
remove unused sstable field
Use range tombstones when dropping cfs/columns from schema

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-5579
clean up inputstreams in finally blocks
patch by Mikhail Mazursky; reviewed by jbellis for CASSANDRA-5580
use nanotime consistently for node-local timeouts
patch by Mikhail Mazursky; reviewed by jbellis for CASSANDRA-5581
Fix NPE in Pig's widerow mode.
Patch by Sheetal Gorsani and Jeremy Hanna, reviewed by brandonwilliams
for CASSANDRA-5488