Fix static counter columns

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-6827
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	CHANGES.txt
	src/java/org/apache/cassandra/cql3/statements/SelectStatement.java
Update syntax for changing caching options.

Patch by marcuse, reviewed by slebresne for CASSANDRA-6745.
Switch CRC component to Adler and include it for compressed sstables
patch by Marcus Eriksson, Radovan Zvoncek, and jbellis for CASSANDRA-4165
add ChecksummedSequentialWriter
Restore expiring->deleted (cell) compaction optimization

patch by Aleksey Yeschenko; reviewed by Sylvain Lebresne for
CASSANDRA-6844
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	CHANGES.txt
fixed bug in CompactionManager.needsCleanup

Patch by Dmitrij Koniajev, reviewed by marcuse for CASSANDRA-6845.
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	CHANGES.txt
Correctly compare BooleanType values other than 0 and 1

Patch by Sylvain Lebresne, reviewed by Tyler Hobbs for CASSANDRA-6779
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	CHANGES.txt
Apply DONTNEED fadvise to commitlog segments
patch by Benedict Elliott Smith; reviewed by jbellis for CASSANDRA-6759
Switch cqlsh from cassandra-dbapi2 to python-driver
patch by Mikhail Stepura for CASSANDRA-6307; reviewed by Aleksey Yeschenko and Tyler Hobbs
prefer Iterators to CollectionUtils
apply BTree update function correctly
patch by Benedict Elliott Smith; reviewed by jbellis for CASSANDRA-6692
clean up Path and Cursor now that we know stack allocation doesn't work as expected
patch by Benedict Elliott Smith; reviewed by jbellis for CASSANDRA-6692
Fix stress to do proper counter reads
Patch by Benedict Elliott Smith; reviewed by Pavel Yaskevich for CASSANDRA-6835
Move ByteBuffer functions to ByteBufferUtil and avoid duplication
add #2635 to CHANGES
Merge branch 'cassandra-1.2' into cassandra-2.0