Should fix sound on most platforms... right now the main issue is the
mixer callback taking too long and causing the DMA to hang or crash on
some systems. Worked around for now with small chunk sizes, permanent
fix would involve moving mixing totally out of the callback. Also
rewrites input code with code taken from rockboy which was also used
in doom, which finally makes it possible to beat the first level!
Finally, cherry-picks a change from Gregory Montoir's `rawgl' to
always succeed on the code wheel verification.

Change-Id: I8df549c923c5075800c6625c36c8202e53de1d27

Co-conspirators: Franklin Wei, Benjamin Brown

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This work is based on:
- Fabien Sanglard's "Fabother World" based on
- Piotr Padkowski's newRaw interpreter which was based on
- Gregory Montoir's reverse engineering of
- Eric Chahi's assembly code

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Progress:

* The plugin runs pretty nicely (with sound!) on most color targets
* Keymaps for color LCD targets are complete
* The manual entry is finished
* Grayscale/monochrome support is NOT PLANNED
  - the game looks horrible in grayscale! :p

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Notes:

* The original game strings were built-in to the executable, and
  were copyrighted and could not be used.
* This port ships with an alternate set of strings by default, but
  can load the "official" strings from a file at runtime.

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To be done (in descending order of importance):

* vertical stride compatibility                          <30% done>
* optimization                                           <10% done>

Change-Id: I3155b0d97c2ac470cb8a2040f40d4139ddcebfa5
Reviewed-on: http://gerrit.rockbox.org/1077
Reviewed-by: Michael Giacomelli <giac2000@hotmail.com>