This PR handles any older config_env files that don't have allowed_media files set. Fixes the bug where a merge of a good list of file extensions was being merged with a null media_ext array, resulting in failed uploads even though all files were actually in the 'good' list.
This PR handles any older config_env files that don't have allowed_media files set. Fixes the bug where a merge of a good list of file extensions was being merged with a
nullmedia_ext array, resulting in failed uploads even though all files were actually in the 'good' list.closes #375