Add platform to all browsers, fixed trailing comma

Added platform to all browsers according to: https://saucelabs.com/platforms
Removed extra comma at line 221
My IDE has different ident apparently so the change looks biggen than it is...

Managed to run almost all browsers here: https://travis-ci.org/SergioCrisostomo/mootools-core/builds/19871445

Travis complains tests are too verbose and Sauce can't find localhost sometimes. A re-start of the build helps sometimes