Two major changes in this commit

+ Shifted all owtf processes to logging module
+ Added owtf process class which can be used to create new processes from owtf

Key points

+ All owtf processes when created will have their root logger modified such that each process writes to a different file along with writing to console
+ OWTFProcess must be extending in such a way that user has to place his code in `pseudo_run` method
Merging branch 'lions_2014' of https://github.com/owtf/owtf into lions_2014

+ Merged changes include changes from Tao, Anand & Viyat