GRIM: Filter savegame list to avoid EMI-saves polluting it.
EMI: Support for datausr.m4b, with gui option
EMI: Draw background layers at intervals

Previously, we split the background layers into everything
before SO 15 and after, and drew like that. However, this caused
the pink ship in shi.setb to not be drawn.

This patch draws the layers of the background at intervals of ten.
So if a set has six layers, layer 5 is the background and 4,3,2,1,0
are rendered at sortorder 40,30,20,10,0.
Merge pull request #733 from somaen/filterGrimSaves

GRIM: Filter savegame list to avoid EMI-saves polluting it.
EMI: Filter savegame list to avoid GRIM-saves polluting it.
EMI: Fix sound doesn't continue after continue pause
GRIM/EMI: Fix EMI localization and optimize parsing of localization-files
EMI: opcode LocalizeString in overwritten in lua_v2
GRIM/EMI: Fix segfault in Localizer constructor
EMI: Add MD5-hashes for German EMI. (Thanks to sirox)
JANITORIAL: Factor out alpha calculation in Actor::draw
EMI: Draw to depth buffer if sortorder >= 100
TINYGL: Support ColorMask

Note, this is just basic support, it is either all or nothing.
Disabling select channels is not possible.
EMI: Draw to depth buffer if sortorder >= 100 (TinyGL)
EMI: Add MD5-hashes for Spanish EMI. (Thanks to secreto)