Bug fixing for last commit.

Needed to add return to predicates.
Adding userscore and backbone dependencies.
Cleanup on JSHint.

Made various classes global in preparation for breaking site.js into
separate files.

Moved some window.resize logic into one place within main() method.
Additional cleanup in preparation for breaking up site.js.
Breaking site.js into one file per class.
Bug fix I introduced into ScrollBoundaryManager during JSHint cleanup.