db/db_iter.cc: remove unused variable

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
db/db_test.cc: reduce scope of some variables

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
db/deletefile_test.cc: remove unused variable

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
table/cuckoo_table_reader.cc: pass func parameter by reference

Fix for:

[table/cuckoo_table_reader.cc:196]: (performance) Function
 parameter 'target' should be passed by reference.

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
table/format.cc: reduce scope of some variables

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
db/db_test.cc: remove unused variable

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
table/block_based_table_builder.cc: remove unused variable

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
document_db.cc: remove unused variable

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
util/cache_test.cc: use static_cast over C-Style cast

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
db/version_set.cc: remove unnecessary checks

Fix for:

[db/version_set.cc:1219]: (style) Unsigned variable 'last_file'
 can't be negative so it is unnecessary to test it.
[db/version_set.cc:1234]: (style) Unsigned variable 'first_file'
 can't be negative so it is unnecessary to test it.

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
ttl/ttl_test.cc: pass const string param by reference

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
document_db_test.cc: pass const string param by reference

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
backupable_db_test.cc: pass const string param by reference

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Merge pull request #327 from dalgaaf/wip-da-SCA-20141001

Fix some issues from SCA
Don't keep managing two rocksdb version

Summary:
Before this diff, there are two places with rocksdb versions. After the diff:
1. we only have one source of truth for rocksdb version
2. we have a script that we can use to get the version that we can use in other compilations (java, go, etc).

Test Plan: make

Reviewers: yhchiang, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D24333
BlockBasedTableConfig Filter policy support RocksJava

As proposed by yhchiang the filter can now be set in Java for
a BlockBasedTableConfig instance.
FilterTest