added a contains shim for Chrome and other browsers lacking this functio...

The Google Chrome browser (and presumably others) have yet to implement the String.contains() function. Thus, Kojak will fail to load properly. This pull request contains a shim which prevents this problem from occurring.

All build tests passed. 
Functionally tested in Chrome 30.0.1599.101 and Chrome Canary 32.0.1676.2.