Change casing from livescript to LiveScript

Hi.

Interpret currently fails at loading LiveScript files because of the (unfortunate) casing of the module :
https://www.npmjs.org/package/livescript vs https://www.npmjs.org/package/LiveScript

Bug found while attending to load a gulpfile in ls.
Merge pull request #1 from Delapouite/patch-1

Change casing from livescript to LiveScript