<Android> PlaylistBuilder Checkpoint

Ability to add playlists into the DB. Need to implement a refresh button
for the main PlaylistActivity to see these changes; current workaround
is to suspend the app and then resume it. (Press home, then click back
into the app)
Merge branch 'master' of https://github.com/Ilikecattle/EECE381Module2
<DE2 & Android> Add several new commands
AddSongToList
RemoveSongFromList