Don't allow null max_hint_window_in_ms
patch by Nate McCall; reviewed by jbellis for CASSANDRA-6419
merge from 1.2
Merge branch 'cassandra-2.0' into trunk
remove dead code
simplify use of columnType, used only for super column types
use StringBuilder correctly
Fix potential assertion error in AbstractQueryPager.discardFirst

patch by slebresne; reviewed by iamaleksey for CASSANDRA-6447
Merge branch 'cassandra-2.0' into trunk
Fix tests
Merge branch 'cassandra-2.0' into trunk
src/java/org/apache/cassandra/hadoop/pig/CqlStorage.java
patch by dbrosius reviewed by slebresne for cassandra-6515