#1944 - Fix possible warnings in legal_file::get_photo_types_by_extension and legal_file::get_movie_types_by_extension.
Added unit tests for these two functions, too.
Merge pull request #93 from shadlaws/fix_1944

#1944 - Fix possible warnings in legal_file::get_photo_types_by_extension and legal_file::get_movie_types_by_extension.