added png support in stores
fixed not recognizing JPG
finalized png support
remove test images
added .gitignore to no accidently commit test files
added Flask-Cors to requirements
simplyfied image resizing
changed size of png test image, so appengine tests are working again
added utils module for format conversion for PIL
added seperate config file for production
added auth_token functionality
fixed bug with uppercase extensiopn
changed travis conf
Merge branch 'master' into feature/imageTypeSupport
fixed diabling etag when file was generated
updated README
Merge branch 'feature/imageTypeSupport'