Adds dataType = 'json' if url contains .json

little improvement on top of Stefano fix.
Merge branch '0.1.9' of github.com:hi-res/theoricus into 0.1.9

Conflicts:
	www/src/utils/string_util.coffee
Merge branch '0.1.9' of github.com:hems/theoricus into 0.1.9
Merge branch '0.1.9' of github.com:hi-res/theoricus into 0.1.9