IndexOf specs

This is intended to fail the build and to give the project direction besides micro optimizations. These tests are taken from `SugarJS`. With this pr I suggest you take the specs and delete the ones you don't wish to support.

Here's a suite you can copy if you want to compete/document the differences from native methods

https://github.com/andrewplummer/Sugar/tree/2fcaabfd837c3365d598f43bbd304ffe4084df2f/test/environments/sugar