included the fastimage gem to the record and playback Gemfile
fixed the nginx definition for the mconf format;

the previous definition was making nginx load from /var/bigbluebutton/published the presentation mconf-default.pdf just because it starts with /mconf
only runs the decrypt script if the get_recordings_url is defined and not empty; removed the logs from the part before checking for the existence of archived/<meeting_id>.done
only includes the playback or download tags on getRecordings response if the formats aren't empty