Removed the use of procedural ids in the whole song list. This required using an each() loop function to go through and set up the buttons after creating the list entries.
Finished commenting loadSongs().
Removed procedural ids from populateSelectedList()
Fixed slider callbacks and their registration to work without the procedural IDs.
Fixed String.contains() error, as well as a few other issues.
Fixed slider and button initialization on the selected themes page, as well as a bug with the timer display.
Fixed interval slider bug.
Unpausing a whole song now resumes, rather than restarting, playback.
File deletion now works without procedural ids.
selection deletion now works without procedurl ids
Sliders now work with re-organized 'selected_song' divs.
Merge pull request #1 from Hamneggs/betterIndexing

Better indexing