Fix for Uglify.js quirk

Replacement for: https://github.com/olado/doT/pull/73

---
The Uglify.js minifyer (used by r.js), compresses doT's global declaration fallback from this:

(function(){ return this || (0,eval)('this'); }()).doT = doT;

into this:

function(){ return this || (0,eval)('this'); }().doT = doT;

Which results in an error in safari/IOS.

Adding a "(0," at the beginning forces uglify to keep the brackets, resulting in working compiled code.