Detects the hostname of the x system starting up and sets the keyboard
default layout accordingly to german or eurkey. Uses either the $HOST or
$HOSTNAME variable, of which the first should typically be set. If no
hostname is detected defaults to eurkey layout. Hostname detection is
hardcoded for now, since I don't anticipate many changes.
Prevents a new instance of xcape being started with every single
shell session (i.e. a lot of sessions with tmux, urxvt, etc.).
Instead initializes xcape key replacement once when starting x
