Refactor of Appender side of things

Refactor of Appenders to allow other logging frameworks in later
Major changes!

Refactored log4jv1 code base quite heavily
Added logbackv1 appender and layout
Created abstract layouts to use with any logging framework:
* logstashv1
* logstashv0 (original)
* gelfv1 (greylog2 - needs some work)
Upped version number to 0.1.0!
Added details to README
Can now specify what log level to print extra details in config. See #2

Cheers :)
Merge pull request #13 from stuart-warren/next

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