coord: divide negatives as supposed, make rendering pixel perfect
codegen: improve unknown enum value error message

new error message:
	FATAL Exception: unknown enum value 'OLD_IDENTIFIER' encountered. valid are: TERRAIN,SHADOW,RUBBLE,UNIT_LOW,FISH,CRATER,UNIT,BLACKSMITH,BIRD,PROJECTILE
	---
	If this is an inconsistency due to updates in the media converter, `make media` should fix it
	---
Merge pull request #145 from franciscod/unknown-enum-value

codegen: improve unknown enum value error message
Merge pull request #142 from franciscod/coord-pixel-perfect

coord: divide negatives as supposed, make rendering pixel perfect
Rewrite of DRS and SLP documentation files.
Merge pull request #130 from LordAro/formats

[RFC] Rewrite of DRS and SLP documentation files.
version: updated for new versioning scheme
Fix assets path in building.md
Add -d argument

It was advertised in the help but it didn't work
Add blegat to authors
Merge pull request #146 from blegat/master

Minor fixes
add debug overlay grid, togglable with F4