Breaking change: Fix and improve control bus set and get functions:

* Fix blatant bug in control-bus-set-range! w.r.t. OSC API
* Remove start and len args from control-bus-set-range!
* Add offset params to allow offsets into multi-channel control buses
* Throw exceptions when invalid offsets are supplied
* Improve docstrings
* Set fns now return the list of vals set