RocksJava should support not only BlockBased Bloomfilter
Improved JavaDoc
Merge pull request #339 from fyrz/bloomFilterSupportNewFormat

RocksJava should support not only BlockBased Bloomfilter
Column family support in RocksJava

This commit includes the support for the following functionalities:
  - Single Get/Put operations
  - WriteBatch operations
  - Single iterator functionality
  - Open database with column families
  - Create column family
  - Drop column family
  - Properties of column families
  - Listing of column families

In addition there is an additional Java sample which can be build
using "make cfsample".

What is not supported currently using RocksJava:
  - Multi Iterator support
  - MultiGet

I decided to file a pull request w/o the missing two features to omit
some merging trouble. I would propose to hand them over to a later point
of time.
Quality improvements
- Replaced all NULL occurences in code with nullptr
- Removed iostream include
Fixed some lint problems
More lint problems fixed
Moved Testing code from Sample to Test.
Fixed line length in Test
Fixed merge inserting whitespaces into Makefile
Small merge correction

Summary:

Test Plan:

Reviewers:

Subscribers:
MultiGet column family extension.
Java6 compatibility
Resolved warnings reported by IDEA
Renamed openColumnFamilies to open method in native bindings
OpenReadOnly support in RocksJava

Changes:
 - new Method: RocksDB openReadOnly(String path)
 - new Method: RocksDB openReadOnly(Options options, String path)
JavaDoc enhancements in RocksDB.open methods
RocksDB ReadOnly support with column families

- openReadOnly extension for column families
- Makefile cleans up now tmp folders properly
- ReadOnlyTest
Making things lint clean
Improved test output, Fixed StatisticsCollectorTest