add external definitions file

Enyo-DCO-1.1-Signed-Off-By: Cole Davis (cole.davis@lge.com)
Adding a bunch of externals definitions.

Enyo-DCO-1.1-Signed-off-by: Blake Stephens <blake.stephens@lge.com>
2 new externals

Enyo-DCO-1.1-Signed-off-by: Blake Stephens <blake.stephens@lge.com>
Several more externals

Enyo-DCO-1.1-Signed-off-by: Blake Stephens <blake.stephens@lge.com>
Added several new externals (mixing, undefined, console), fix Date.now