handle decodeThread restart
recirculate the frame buffer
update status on every frame, triggers next frame
OneShot callbacks, plug debugging output
send Progress update for qrcode not found
Merge branch 'master' into ticket-38

Fixed conflicts in:
	development/android/qrstreamlib/src/main/java/com/galois/qrstream/lib/Preview.java
	development/android/qrstreamlib/src/main/java/com/galois/qrstream/lib/Progress.java
	development/android/qrstreamlib/src/main/java/com/galois/qrstream/lib/ReceiveFragment.java
Job prints message title and mimetype
Merge branch 'master' into ticket-38

Conflicts:
	development/android/qrstreamlib/src/main/java/com/galois/qrstream/lib/ReceiveFragment.java
Remove unused Picture class
Merge branch 'master' into ticket-38
Request camera preview frames from within qrlib's decodeQRcodes
Failed frame notification not necessary
Remove sample qr code from resources directory
Ignore messages received after Rx fragment is no longer visible.
Modify how and when DecodeThread gets started.
Added cancel button -- although it is not the right size
Scale the cancel button better
Changed ActionBar to overlay. Fixes squishing of display and closes #55
Fixes potential memory leak and lint warning with displayHandler
No need to fully qualify camera type
Make button local variable