Upgrade UglifyJS to address issues

[robbytx]

In particular, this appears to resolve:

• Mangling named functions in strict mode can cause syntax errors in Safari mishoo/UglifyJS#179

[sirugh]

Isn't uglifyjs2 the NEWER version of uglifyjs? This is a scary change.

[tnunamak]

Yes, but it appears that the uglify-js package is actually now UglifyJS2 if you install a 2.x version (and actually, there's a version 3 now, but still in the UglifyJS2 project, if you want to be even more confused).

[robbytx]

@sirugh npm install warns:

npm WARN deprecated uglify-js2@2.1.11: You can now install this using uglify-js@2.2.0 node_modules/uglify-js

So, uglify-js@2.2.0 (and beyond) actually supercede uglify-js2@2.1.11

[robbytx]

Do I need to upgrade package.json in my commit?

From a semver perspective, would you consider this a patch release? I'm not sure what all changed in uglify-js from 2.1.11 to 2.8.22, and whether those changes would indicate this change is a minor release.

[sirugh]

@robbytx This is a patch, but we will handle that in the "release".

[robbytx]

@KikoRamos has verified this in BV Conversations against supported browsers, and I've verified this in our in-development application.