Remove core/index.js change requirement.

Knockout was used to move all server side config into the client side.
Eventually the theme will use AngularJs, but knockout works better with
the current mix of technologies.

Merged changes from community:
- Google analytics can now be completely customized in config.js.
- Social links can be fully specified in config.  Removing links simply
requires them to be removed from the config.
- Search is right aligned