Only stop if the transition on this element ended

This way it doesn't end when some random element elsewhere on the page has an ending transition.

It must be noted that this is not a complete fix. If you have multiple transitions on the element, it still ends when the first ends.

I ran into this not working (the transition ends almost immediately, because some unrelated transition ends). This fixes it for me, but I was wondering whether this cornercase was considered, and whether the other cornercase (multiple transitions) was considered.

I think it's very hard to get this correct, and think it might be better to make the timeout explicit, or at least allow to set it explicit, and fall back to this behaviour. But I'm really interested in feedback on this one.
Added event parameter
Make sure it works when we have no css transitions
add picture element and related attributes
add picture to xjs.knownTags
use attribute for media, srcSet and sizes
Add newline before JSX spread when appropriate

Previously, we were losing the newline before a JSX spread attribute which would cause the lines to not match up; this fixes the problem.
Fix DOMProperty bitmask checking
Comment typo
Reduce unnecessary warning while including JSX transformer in browser
Merge pull request #2116 from spicyj/nl-jsx-spread

Add newline before JSX spread when appropriate
Update video.md with Forward JS 2014 talk

Added "React and Flux: Building Applications with a Unidirectional Data Flow" by Bill Fisher and Jing Chen.
Correct highlighted block
Move htmltojsx.js to React-Magic project.

The HTMLtoJSX file is really a part of the React-Magic project, and should belong there rather than here:
 - It doesn't really follow the release cycle of React at all
 - It is totally standalone with no dependency on React
 - The only usage of this script is in React-Magic and on the HTML to JSX page on the React website (http://facebook.github.io/react/html-jsx.html)

I've hotlinked it from the Github site for that project since this was the easiest way to pull it in.

Due to the fact that Github Pages lacks redirects (among other basic web hosting functionality), I've replaced the `html-jsx-lib.js` file with a comment explaining where the file has moved to, just in case anyone was hotlinking it from the React site.
Merge pull request #2156 from simonwelsh/patch-1

Correct highlighted block
Merge pull request #2155 from rickbeerendonk/patch-1

Update video.md with Forward JS 2014 talk
`console.warn` when html-jsx-lib.js is loaded
Merge pull request #2158 from Daniel15/htmltojsx-move

Move htmltojsx.js to React-Magic project.
Don't wrap values with ReactTextComponent in traverseAllChildren
Remove calls to `Range.detach`

This method is a no-op, as demonstrated by console warnings in Chrome and https://developer.mozilla.org/en-US/docs/Web/API/range.detach.

Remove callsites.

Fixes #2142