Add rule for handling artists ending in .
User case: a user listens to R.E.M.
Right now, bliss moves media into a folder R.E.M_
This is not what the user would like because underscores are ugly and we have sensible file systems in 2016
The user might prefer that:
a) You don't try to help them "fix" this issue. Directories can end with a _.
b) You let them configure what to do, e.g. R.E.M. -> R.E.M or REM or whatever.
We should maybe be a bit smarter about this, because it depends on the OS. Windows shell doesn't like trailing periods, see https://msdn.microsoft.com/en-us/library/aa365247(VS.85).aspx - "Do not end a file or directory name with a space or a period."
But if you're sure you won't be accessing from a Windows machine, I suppose that could be relaxed.