Some porting work on Lucene 4.3, broken!
More porting work, still broken.

Focusing on Utils namespace now first
More Util work
Finish CollectionUtil
Add CommandLineUtil
DocIdBitSet, DocIdSetIterator, Constants
Add DoubleBarrelLRUCache
Port: FieldCacheSanityChecker, FixedBitSet
Port: Add InfoStream, IntBlockPool

Mark IndexableBinaryStringTools as obsolete, move IdentityDictionary to
Support
Port: Add IntsRef
Port: add IOUtils