Implement bar option: id <custom-id>
Implement bar option: id <custom-id>

If the id is defined by another bar it will just use the default id for
the bar. Typically `bar-x`.

If the id command is used multiple times within a bar block, the last
one will 'win'.

sleep-walker/sway,1ace/sway,johalun/sway,colemickens/sway,SirCmpwn/sway,ascent12/sway,crondog/sway,ptMuta/sway,taiyu-len/sway,mikkeloscar/sway,colemickens/sway,taiyu-len/sway,4e554c4c/sway,taiyu-len/sway,colemickens/sway,mikkeloscar/sway,1ace/sway,ascent12/sway,ascent12/sway,sleep-walker/sway,crondog/sway,4e554c4c/sway,1ace/sway