update some loop logic, fix readme, release 0.2.4, feature inverse, release 0.3.0

Changed .forEach to native for loop for speed and compatibility with older browsers(~IE8).
- [jsperf speed](http://jsperf.com/for-vs-foreach/66)
- [compatibility](http://stackoverflow.com/questions/156696/which-web-browsers-natively-support-array-foreach)

Fixed readme Typo, missing closing tag

Update versions

you don't need the else here, both branches end with `return ( inverse );`