removed InbuiltSecondaryIndexHolder and made SSTR responsible for it's suffixArray files
moved the cache of SSTR->OnDiskSA into SASI (from SSTR), and fixing bugs related to not setting the comparator correctly.
bug fixes
fix bounds checks for OnDiskSA.iteratorAt(...) (+ tests)
reload sa files at startup - needs some cleanup, it works
fix bounds checks for OnDiskSA.iteratorAt(...) (+ tests)

Conflicts:
	src/java/org/apache/cassandra/db/index/search/OnDiskSA.java
	test/unit/org/apache/cassandra/db/index/search/OnDiskSATest.java
WIP - getting SASI initialization after restart working correctly (... still)