adding tetrahedron example
more comments
Fixed tetrahedron vertex coordinates
Lined things up
took out debug code, moved ignored eamples to examples .gitignore
added tetrahedron and modelfile to ignore
new .gitignore inside environments
Merge branch 'master' of https://github.com/2-complex/g2c into tetrahedron

Conflicts:
	environments/.gitignore
	examples/.gitignore
	g2c/graphics.cpp
readding .dSYM to .gitignore
Merge branch 'tetrahedron'