[beta] Version 0.2.0 beta 1

This seems to be a rather stable version. After this the event handling
(and overall state) starts to behave in strange ways (a single bad
commit could not be identified).

This version misses some interesting options from the development
version (reversed fixed levels, strobe, reliable LVP). Use this version
instead of v0.1.1 if you want the beacon mode.