Major refactoring

Switched to Maven build system. Refactored to ASM 5.0.3 and updated use of deprecated code. Fixed build for JDKs 7 and 8. Ignored test that relies on creation of a signed jar where a class loader which assignes a protection domain should be used instead.

On a side note, the code base is still not in a great state, I would not recommend to use cglib before some of the issues I found are fixed. There are around 50 TODOs which partly reference severe errors, the test coverage is marginal and the overall quality of the code and its comments is not too great either. There is still a lot to be done.

I tested this build on JDKs 6, 7 and 8. I hope that Travis and maybe someone else can verify this.