Made the text drawing support non-strings

Accidentally passing of a number to the text of an element produces a
very nondescript error, which made debugging an extremely lengthy
process.

Instead, I changed the code to accept any type of object (although
string is still preferred). It will automatically call the object's
toString() function when converting for the canvas.
Merge branch 'master' into fix-editor-incompatibilities
introduce reg-point back among with pivot
Merge pull request #106 from Animatron/reg-point

Return of a registration point for special purposes
Merge pull request #104 from ahollenbach/master

Supporting non-strings in text elements
fix PR #106 from @ahollenbach
Merge branch 'master' into game-dev

Conflicts:
	src/player.js