How to compile a library from source

I recently upgraded to the new version of processing version 3 and the control p5 library no longer works. On the author's site there is a link to the old version but apparently there is a new version that works with processing 3 but is only available through github as a source code. I also tried contacting the author but the email address bounces back. I am not very familiar with java or how to compile it to be usable in processing. I followed several tutorials but the errors that eclipse throws are incomprehensible and not very helpful. Any help would be appreciated.