Add hadoop progressable compatibility.
Patch by Ben Coverston, reviewed by brandonwilliams for CASSANDRA-5201
FBUtilities.singleton() should use the CF comparator

patch by slebresne; reviewed by thobbs for CASSANDRA-6778
Fix CQLSSTableWriter.addRow(Map<String, Object>)

patch by slebresne; reviewed by thobbs for CASSANDRA-6526
Fix timestamp scaling issue for 6623
update cobertura version
patch by Ed Capriolo for CASSANDRA-6800
Fix HSHA server introducing corrupt data

patch by xedin; reviewed by slebresne for CASSANDRA-6285
Fix CAS conditions for COMPACT STORAGE tables

patch by slebresne; reviewed by iamaleksey for CASSANDRA-6813
Update version, news and license for 2.0.6