Event revamp

[Antonio-Laguna]

This adds a bunch of improvements and bug fixes. I've tested this on all browsers I could, including IE11 just to be extra sure all tests pass on all browsers since events have been heavily changed.

• Removed phantom dependency to run tests. Want to be able to run tests on browsers to avoid further issues.
• Added private data cache. Really simple. Intended to be used with Node elements. Probably better to add stuff there instead of using data attributes since we're modifying the DOM. (It is, but is a small amount https://jsperf.com/data-vs-virtual)
• modify event usage seemed broken, fixed.
• Added Namespace support. Note that I didn't do nested namespaces since I don't think that's an usecase we're going to have and would mess the code a bit.
• Fixed the case in which you couldn't unbind when more events of the same type had been already attached.
• Added the ability to remove a single event handler vs all.