removed unused helper
picture geometry now has it's own file and a flexible constructor
moving storage related stuff into it's own class
minor fixes
adding unit test for gm scaling param
renaming to_size function to gm_size_param_from

This matches the current situation better - we hand it the original size of
the image.
refactored scaling logic
minor: changing vars for no scale needed to simplify conditions
removing scales as they are only used in one place
consistent naming for gm_size_param_for(orig_size) and gm_crop_param in Picture::Geometry
Merge branch 'develop' into feature/cleanup-with-codeclimate
Merge pull request #15 from Crabgrass/feature/cleanup-with-codeclimate

Cleanup with codeclimate