Switch to FuelUX as widget library, remove jQuery UI entirely

FuelUX is an extension to Bootstrap and contains bootstrap. Used
so far to create nice spinner controls for the PID settings.

Also removed dependencies on jQueryUI which does not play nice with
Bootstrap/FuelUX and implemented custom power slider (no handle for now
I like it that way).
Bug fix: switch to FuelUX caused edit loco and layout to fail.

Also small progress on PID settings UI
Backtrack: FuelUX did not work as well as expected.

Used a dedicated bootstrap numeric spinner instead. More lightweight
and actually works, whereas the FuelUX spinner did not work for decimal
places at all - tons of weird bugs.