GRIM: Fix going to fullscreen in the demo
EMI: Implement screenshot thumbnails for savegames
GRAPHICS: Initialize/Destroy _storedDisplay
OPENGL: remove GLU leftovers
BASE: correct to official description
ALL: unify setupScreen() arguments type
EMI: Free materials as soon as they are no longer in use by any costumes.
SDL: added safeguard for clearOverlay() if overlay is closed
SDL: don't call error() inside setupScreen(), it will crash if debugger is used
GRIM: Implement the getDebugger API

This allows errors to be shown in the debugger
EMI: Implement projection shadows.
EMI: Calculate actor bounding box correctly.

This is necessary for Actor::shouldDrawShadow to behave correctly, but
could also affect collision detection.
EMI: Enable shadow sprites.
GRIM/EMI: Make Light and SetShadow structs instead of classes.
GRIM/EMI: Use Doxygen style for the comments.
EMI: Implement projection shadows for OpenGLS renderer.
GRIM: Initialize _shadows to null.
EMI: Do not print a warning if Actor::getBboxInfo is called for an actor that doesn't have a model.
OPENGLES/SHADERS: minor cleanup comment
Merge pull request #956 from Akz-/emi-shadows-rebase

EMI: Implement shadows for OpenGL and TinyGL renderers