First attempt to switch from disk to S3 caching.
Add boto as requirement for funsize deployment.
Small fixings, docstrings in cache.py
Remove verification_file.csv as it is useless at this moment.
Refactoring in funsize/backend after S3 switch.
Refactoring in funsize/configs after S3 switch.
Refactoring in funsize/frontend after S3 switch.
Refactoring in funsize/utils after S3 switch.
Remove complete mars from caching as they no longer have sense there.
Bugfix in caching.