New script function: GetPXSCount.

Counts number of loose pixels of a material in an area.
Added new ambience object to Experimental.ocd.

Controls the music playlist according to the situation the player's clonk is currently in.
Build fix
Use COMMENT (not COMMENTS) as the category field to select songs when using SetPlayList.
Move FlightlessBird from Objects.ocd to Experimental.ocd.

Moved because it causes annoying errors on startup. It's not even a full definition and the material doesn't seem to be used anywhere.
Added GetPXSCount to docs.
Fix music fading when fading back to the same piece that is currently fading out.
Do not fade out music on scenario section loading.

Instead, scripters can use SetPlayList() or Music() to fade music by script if desired.
Added ambience test version of DeepSeaMining.
Fix build on 32-bit architectures
reduce version numbering from x.y.z (x does never changes) to y.z
Remove Sort field from C4FolderHead

This field apparently was intended to be used in folder maps, but was
already unused in Clonk Rage, and has never been used in OC either.
increase game content version entries to 6.0
Squelch varargs warnings in System.ocg

The engine (extra)warns whenever you use Par() or ... inside of a
function that is not declared as taking a variable number of arguments.
Change the declaration of all System.ocg varargs functions so it is
immediately obvious.
Fix assertion when drawing boxes on non render targets.

This doesn't fix material preview in editor mode yet but at least there's no more assertion. We should probably create a proper render target surface for that.
Log information about GPU used by OpenGL on startup.
Auto-select nVidia GPU on Optimus laptops.

Since we're no longer using DirectX, nVidia's automatic detection no longer works classifies OpenClonk as a game to use the high performance GPU. Note that this flag does not work on some old drivers (version<302 according to specs). To support these old drivers, we would have to link against DirectX despite not using it.
Fix Win32 MinGW build.

I hope...
Fix texture preview in editor tools dialogue on Windows.
Fix scroll bars in zoomed editor viewports on Windows.