Add skeleton for !song, re-work of SR commands

!wr and !leaderboard both moved to non-local resources.  !wr now uses
speedrun.com for all lookups, and !leaderboard hits SRL api to get the
abbreviation and then append it to a speedrun.com link (results may
vary).  Small function changes to try and make things more DRY, more to
come for this aspect.