Listen for Reporter to flush bundle, then clear the cell count on next
scan.
Timer was calling broadcastsync on the timer thread, and in general,
doing a bunch of other thread-unsafe access. Made this thread-safe
through use of a handler. (A handler is on the thread where it is
created).
Merge branch 'dev' of https://github.com/garvankeeley/MozStumbler into 1067-cell-count-fix-v2

Conflicts:
	android/src/main/java/org/mozilla/mozstumbler/service/stumblerthread/scanners/cellscanner/CellScanner.java
Merge pull request #1085 from garvankeeley/1067-cell-count-fix-v2

1067: Better fix: Listen for Reporter to flush bundle, then clear the cell count on next scan.