Reorganize the driver module for more clarity.
Added locking suport to bartendro so that only one person at a time
can make drinks.
Still need to allow the user to close the bartendro busy box, but the
box is nicer
Return proper number of arguments, even during an error
Changed test dispense to use the bartendro lock.
Checking in Issue #64 migitation code. Still no idea what causes that.
Only show liquid level UI elements if the liquid level sensors are
enabled.
Added a debug page and moved the "test dispensers" button to it.
Also finish implmenting the hiding of the liquid level stuff.
Created the HTML for a new liquid level page
Use the term liquid level sensor, not liquid out.
Finished tweaking the HTML/CSS for the liquid level sensor page
Missed on _send_packet8 reference
Merge remote-tracking branch 'upstream/master'

Conflicts:
	ui/bartendro/__init__.py
	ui/bartendro/view/ws/drink.py
	ui/bartendro_server.py
	ui/config.py.default
	ui/content/templates/admin/layout
	ui/content/templates/admin/liquidout
	ui/content/templates/drink/index