replace 'window' with 'self' in src/three.js for both NodeJS and IE10 compatibility.
'window' to 'self' in npm header.
move clock support for NPM from header.js to THREE.Clock.now.  Rename 'window' to 'self'.
simplify THREE.Clock.now based on @mrdoob's suggestions here: https://github.com/bhouston/three.js/commit/72e1ce3bf3e895494b0482464f9d89a05dccaefe#commitcomment-3115324
Merge remote-tracking branch 'bhouston/npm-cleanup' into dev