doc: uniform terrain rendering formula added
doc: added coordinate-system doc
convert: moved binpacking function to util
doc: update coordinate-systems doc

added info on how coordinates in different frames are represented
(int, float, ...)
convert: exporting blendomatic modes as packed images
convert: fixed rounding error for atlas packing
Merge branch 'master' of git.sft.mx:openage
doc: updated implementation/coordinate-systems

changed terminology
removed coord_window
renamed coord_game to coord_phys
changed representations of coord_phys and coord_hud
engine: added coordinates header

defines coordinate structs in accordance to doc:implementation/coordinate-systems
doc: blendomatic masks inverted for more intuitive usage
engine/terrain: importing blendomatic masks
doc: updated implementation/coordinate-systems

changed unit 'thu' to 'teu'
engine/terrain: drawing blending masks at matching positions
engine/terrain: converted binary to hex values
engine/terrain: using redundancy minimizing blend tiles

for the adjacent direction blends, there are 4 tiles per direction.
we now make use of them.
engine/terrain: respecting diagonal influence tiles now
engine: introduced coordinate systems

vector2.h, vector3.h, coordinates.h, coordinates.cpp contain coordinate system
and coordinate system transformation code.

all other files have been updated to use the new coordinate systems/structs;
no (x,y) variable pairs should be remaining in the code.

the camera position has, however, not yet been integrated into the code,
as have the phys coordinate calculations
engine/terrain: taking account of blending priorities

also activated diagonal influence tiles, they are drawn too
frequently though.
convert: enabled converting alpha masks per default
engine/terrain: disable diagonal blending if adjacent blending active