Call states should clearly identify all actors

[marcoscaceres]

The call states are currently written in passive voice, as such, it's not clear who the actors are in each state (on a careful reading, it's hard to know what part of the system is doing what). It would help a lot to rewrite these in active voice, clearly identifying who the actors are.

[marcoscaceres]

@zolkis, if you have time, will need your help with this one.

[zolkis]

OK. Just that now I have some priority work to do.

[marcoscaceres]

No probs, it's not high priority. BTW, when you can, please ping me on IRC so we can discuss how to move forward with constructors, promises, and TelephonyService.