* Remove `m.prop` + `m.withAttr`
- For many uses, `m.withAttr` is *more* verbose than just directly using
an event handler
- If you're using it with a bound callback, you're literally wasting a
single character in the human readable version (and you're *saving*
them in the minified output).
- It sometimes obscures your intent, if overused.
- Functions are easier to compress than `m.withAttr`, resulting in
slightly smaller bundles.
- `m.withAttr` is overused anyways.
- `m.prop` is basically useless without `m.withAttr`, and the API
doesn't have the same benefits it had with 0.2.x.
* Update changelog
