Fix IPython version check by gevent inputhook
Allow KeyboardInterrupt when gevent is enabled
Enable interrupting parameter accessors

for getters just silently exit and by setters allow the parametrizable to have
_cancel_param method for reverting the setter effect.
closes #330
Make devices abortable

which means bring them to some safe state.
Implement _abort methods in devices
Enable aborting all devices from a concert session
Add abort tests
Implement parameter setting cancellation in motors
Enable interrupting future's join and result
Add cancel_operation to futures for cancel cleanup
Add cancel_operation test
Cleanup after async parameter setter interruption

with proper cleanup.
Update the docs
Don't monkey patch if gevent is not enabled
Merge pull request #332 from ufo-kit/add-abort

Emergency stop and parameter cancelling