[RocksJava] Support for stored snapshots

Summary:
RocksDB supports two ways of saving snapshots. In
memory and on disk. The later was added with this
pull request to RocksJava.

Test Plan:

Reviewers:

Subscribers:
[RocksJava] Sigsegv fix for MergerOperatorByName
[RocksJava] Incoroporated changes for D29013
[RocksJava] Addressed comments in D28971
There will also be a librocksdbjni-osx.jnilib.dSYM folder on MacOSX
builds to be deleted
Do not delete Java Fatal Error Log, developers may still want these for
reference
Merge pull request #425 from adamretter/macosx-clean-fix

Mac OS X jclean fix
Block ReadOnlyDB in ROCKSDB_LITE

Summary:
db_imp_readonly.o is one of the big obj file.  If it's not a necessary
feature, we should probably block it in ROCKSDB_LITE.

    1322704 Nov 24 16:55 db/db_impl_readonly.o

Test Plan:
make shared_lib -j32
make ROCKSDB_LITE shared_lib -j32

Reviewers: ljin, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29583
Merge pull request #401 from fyrz/RocksJava-Sigsegv-MergeOperatorName

[RocksJava] Fixes in MergeOperatorByName
Merge pull request #398 from fyrz/RocksJava-CreateCheckPoint

[RocksJava] Support for stored snapshots
[RocksJava] Fixed MacOS build of RocksJava

There were still some precision loss problems
remainging in RocksJava. This pull request resolve
these.
Block Universal and FIFO compactions in ROCKSDB_LITE

Summary: Block Universal and FIFO compactions in ROCKSDB_LITE

Test Plan:
make shared_lib -j32
make OPT=-DROCKSDB_LITE shared_lib

Reviewers: ljin, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29589
Merge pull request #426 from fyrz/RocksJava-Restore-PrecisionFix

[RocksJava] Fixed MacOS build of RocksJava