* Fix issues 77, 87, 182, 190, 200, and 201
* Fix bug described in https://groups.google.com/d/msg/leveldb/yL6h1mAOc20/vLU64RylIdMJ
* Fix a bug where options.max_open_files was not getting clamped properly.
* Fix link to bigtable paper in docs.
* New sstables will have the file extension .ldb. .sst files will continue to be recognized.
