cosmetic refactoring
tests for PhotoFile.photo_file? (different cameras filename patterns)
removed rails3 variable (deprecated on rails4)
removed new/create methods from photo_files_controller, fixed update and photo_file_params methods
PhotoSharingHelper to PhotoSharingsHelper
removed checksum from photo_files form
photosharing to photosharings at photo_sharings#edit
photo_sharing to photo_sharings in routes
updated dimensions test fixtures
updated exif_info's test fixtures
functional tests for photo_sharings_controller
functional tests for photo_files_controller
improving photo_sharings test fixtures
improving photo_files test fixtures
improving origins test fixtures
added secret_key_base (replacing secret_token) into secret_token.rb
fixed photo_sharings#show
removed new link from photo_files#index
removed new link from photo_sharings#index
fixed photo_file urls on photo_sharings#_form