Use BlaSingletonMeta for the BlaUniqueWindow class

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
Move window classes into blawindows.py

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
Fix crash due to xid corruption

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
Refactor shutdown sequencing

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
Fix bug causing playlists appear to be filtered

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
blaplaylist.py: rename filter hbox

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
Fix two unhandled UnicodeDecodeError exceptions

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
Make blapreferences.py PEP8-compliant

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>
Drop mmkeys dependency in favor of keybinder

Signed-off-by: Niklas Koep <niklas.koep@gmail.com>