dbus-python: add pure python mainloop
service.openelec.settings: switch to dbus.mainloop.poll

highly experimental. do not use.
bluetooth not tested and is likely broken
dbus-python: bye bye dbus-glib
remove package: dbus-glib
remove package: pygobject
glib: build static libraries

used only by udevil and connman. 2.7M shared vs 300k static. meh