Bugfixes for bash-completion, xrandr output parsing and "cannot fint crtc for output"

bash-completion:
- Prevent "No such file or directory" when ~/.autorandr does not exist

current_cfg_xrandr():
- Fix xrandr output parsing when the "primary" column is present.

load_cfg_xrandr():
- Workaround "cannot find crtc for output" by issuing two xrandr commands: one for disabling outputs and one for enabling.