Hooks for image processing development
(Hopefully) improved the puzzle board recognition algorithm.
More changes of puzzle board recognition
New UI.
Accommodated with some lint warnings.
Merge branch 'ui'
A new OpenCV initialization.
New OpenCV Initialization code built into the app.
Added a shortcut to OpenCV initialization for the second or later calls.

The way MainActivity initializes OpenCV is changed again.
The capture button is always enabled, and pressing it after declined
installing OpenCV Manager asks the same thing again.
Added some comments.
Merge branch 'master' into ui
Added title to "Download OpenCV" dialog.
Merge branch 'master' into release

Conflicts:
	res/values/strings.xml
Prepare for 0.80 release.