Read signing info from gradle.properties.
Cleanup code around images. Add initial toolbar code.

This change stops activities from knowing about HighlightingImageView,
moves certain pieces of logic from the ImageView to ImageAyahUtils,
and makes the page scaling data cached across instances. It also
fixes a bug where highlighting data was slightly off after switching
orientations from landscape to portrait.

In addition, this commit adds the initial AyahToolBar class and related
display logic. The code to display this is commented out since it's not
done yet.
Hookup actions to AyahToolbar and move tasks to separate package
Merge pull request #379 from afarra/master

Hookup AyahToolbar
Check in gradle.properties with some signing values.
Improvements to toolbar placement code.

- use NineOldAndroids for animation and View helpers on 2.x
- fix the y position of the toolbar being slightly off
- fix selection on tablet when two pages are showing
- update strings to add open source credits
Update README file
Upgrade to the latest gradle plugin, and use SDK Manager.

Jake Wharton's SDK Manager plugin for Gradle will manage setting up
up local.properties and keeping the various dependencies, sdks, etc
up to date. This should make it easier for people to build.

This fix also helps by making the Crashlytics plugin always enabled,
whereas before, we'd enable it manually for release builds and keep
it disabled for debug builds.
Favor using submenus over using two separate menus.
Move ayah toolbar with page swipes. End Ayah mode when switching to translation view.
Undo changes to SlidingUpPanelLayout's onTouchEvent
Improve Ayah mode navigation and flow
Fix: Fragment TagBookmarkDialog{43abd050} not attached to Activity
Merge pull request #380 from afarra/master

Move ayah toolbar with page swipes
Initial arrow implementation for AyahToolBar.
Fix sliding issues with slider and allow arbitrary positions. End ayah mode when swiping more than a page away.
Handle scrolling the toolbar when scrolling quran page
Get rid of float array and fix slight bug with vertical scrolling sync
Merge pull request #381 from afarra/master

Fix sliding issues with slider and allow arbitrary positions
Fix highlight scrolling issues