Add support to JSX transform for <hyphenated-tags>

This only adds support for whitelisted tags, not arbitrary ones.

Closes #1539
Support more properties for image maps

Supporting the `<area>` tag is pretty useless if we don't support the necessary properties.
add count() method to ReactChildren

added ReactChildren.count() to count the number of children, and a test case.
Cleanup ReactChildren
Remove jest usage in ReactDescriptorTest

Until we're only using jest on github, we should stick with Jasmine spies. Soon, hopefully.
Stop running so many things in travis

We're not actively looking at most of these and they take up valuable
job time.