Update icons (#116, thanks doopl!), docs, licenses.

Also use better phrasing for long-press instruction.
Merge pull request #138 from doopl/master

Completed popup menu visual improvements
Abandoned: GridLayout
Fix #134 (the rest of). GridLayout, animations, stars.

Also never needs to recreate Views any more, which is nice.
Show action bar text on 480dp width; stop grid/list toggle disappearing on use on 2.1.
Just on the gameplay screen, use the chooser-style icon as Up.

Provides a clearer indication of function, keeps it monochrome and non-distracting, lets the leftward arrow be seen more clearly.
Fix #141: re-enable German docs.
Back from gameplay -> chooser.

Requires that chooser is already started, which the next commit will sort out.
Fix #38: create chooser in a forwarding activity.

The rename dance ensures that existing home screen shortcuts etc. to SGTPuzzles are still valid.
Better stars, pad chooser headings, remove unused imports.
Fix #142: choosing the game you've not finished yet allows resume.

As a side-effect, remember "ever completed" state and resurrect the popup on returning to the app.

This can look silly if you've completed, made further "losing" moves without undoing your completing move, and *then* you leave and return... but I'm not that bothered.

Should probably switch to using midend_status() at some point.
Fix #143: cancel doesn't go to chooser unless you came from there.
Sort out some release build/lint failures (for #139).

e.g. don't have a values-de since we only have the docs in German, not the UI.
Fix first ever choice of game, broken by d879a4fe37638ab02961a4744a1ce142adf7e7e7.
Fix #145 (German docs).
Move help to an ActionBarActivity

- Has a modern appearence, congruous with the rest of the app.
- Allows for up navigation on action bar so the user doesn't have to back
  through every page viewed when they want to escape help.