[RocksJava] LogLevel support in Options

It's now possible to set a LogLevel in Options and
DBOptions to control LOG verbosity.
[RocksJava] Incorporated review comments D28947
[RocksJava] Bump version to 3.8 in rocksjni.pom
[RocksJava] MVN Build reads version from version.h
Merge pull request #399 from fyrz/RocksJava-Version-to-3.8

[RocksJava] Bump version to 3.8.0 in rocksjni.pom
Minor tidyup and use Java 7 for file copying
Make sure to use the correct Java classloader for loading the RocksDB
Native Library
Merge pull request #396 from fyrz/RocksJava-LogLevel

[RocksJava] LogLevel support in Options
Improve the comment in InfoLogLevelTest.java

Summary:
Improve the comment in InfoLogLevelTest.java

Test Plan:
make rocksdbjava
Merge pull request #402 from adamretter/bugfix-native-library-loader

Use correct classloader in Java NativeLibraryLoader
Fixed a bug which could hide non-ok status in CompactionJob::Run()

Summary: Fixed a bug which could hide non-ok status in CompactionJob::Run()

Test Plan: make

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D28995
[RocksJava] JavaDoc corrections - Java8

This commit solves build problems in Java8 due
to wrong JavaDoc.
Merge pull request #406 from fyrz/Build-Fix

[RocksJava] JavaDoc corrections - Java8
[RocksJava] GetIntProperty in RocksDB

Expose GetIntProperty methods to RocksJava. As the integer(64-Bit)
value is no integer in Java the method is aligned with the return
type which is long.
[RocksJava] Improved comments in RocksDB class

Improved comments in RocksDB getLongProperty methods,
to describe the behavior more detailed.
Merge pull request #397 from fyrz/RocksJava-GetIntProperty

[RocksJava] GetIntProperty in RocksDB
Options helper supports k, m, g, and t unit suffixes

Summary:
Add unit support in options helper so we can specify, e.g., 10m for
10 megabytes.

Test Plan: Updated options_test

Reviewers: sdong, igor, ljin

Reviewed By: ljin

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D28977
remove cfd->options() in DBImpl::NotifyOnFlushCompleted

Summary: We should not reference cfd->options() directly!

Test Plan: make release

Reviewers: sdong, rven, igor, yhchiang

Reviewed By: igor, yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29061
remove all remaining references to cfd->options()

Summary:
The very last reference happens in DBImpl::GetOptions()
I built with both DBImpl::GetOptions() and ColumnFamilyData::options() commented out

Test Plan: make all check

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29073
[RocksJava] Convenience methods for Options

RocksDB introduced in 3.7.0 convenience methods
for getting ColumnFamilyOptions and DBOptions
instances from predefined configuration structures.

There is now also a method in RocksJava to load DBOptions
as well as ColumnFamilyOptions from a predefined Properties
based configuration.