Update CONTRIBUTING.md
Fix typo in UMD.  Fix missing dev dependencies.
Update CONTRIBUTING.md
Ensure that elements have the right opacity.

When an update.transition event is called soon after the
enter.transition event, the fade-in transition is cancelled, which
leaves the element with a low opacity. This commit ensures that
update.transition makes the element fully opaque in all situations.
Bump to 0.1.6.
Merge branch 'master' into convert-to-js

Conflicts:
	bower.json
	package.json
	src/layer/col-header.coffee
	src/layer/row-header.coffee
	src/layer/thread.coffee
	src/meta/intro.js
Bump up version to 1.0.0-alpha
Update readme and contribute