FIX: geolocation setup sequence

- register geolocation button click listener on start
  to use custom location even if current location request
  will never be received
- remove unsolicited event workaround
  (it's not working, packets stucked in queue until another
  unsolicited event will be sent, e.g. appUpdateRequest)
- new geolocation setup workflow
    geolocationReady (CLIENT -> ACTOR)
    r2d2b2g:geolocation-ready (ACTOR -> SHELL)
    r2d2b2g:geolocation-update (SHELL -> ACTOR)
    geolocationRequest (ACTOR -> CLIENT)
    geolocationResponse (CLIENT -> ACTOR)
Merge pull request #436 from rpl/fix-geolocation-ready

FIX: geolocation setup sequence