Add ability to do a more traditional bspwm startup (using the bspwm-session
script provided by nixpkgs.bspwm) as an alternative to directly starting
sxhkd & bspwm
Also added the ability to specify a custom startup script, instead of
relying on the provided bspwm-session
add '-f 100' as an argument to sxhkd to keep it from flooding bspwm
add SXHKD_SHELL=/bin/sh to help default to a faster shell than what may
be set in $SHELL (example: with zsh)
Now the default way to define NixOS window manager modules is to use
mkEnableOption to describe the module itself.
In this commit, all files on nixos/modules/services/x11/window-managers
are changed.
