Javadoc tweaks.
Some work on context docs.
Remove the use of List<Handler> and make the API more consistent in a few places.

This simplifies the API and will also support hot reloading of chain building actions in the future.
Cleanup of ChainBuilder.
Set ratpack.reloadable in development for Java apps too (#32).
Detect changes chain building actions and rebuild (#32).

Note: not sure how to test this at the moment.
Use different method variant.
Extract method.
imports.
Some doc fixes.
Support reloading of handler factories and module actions (#32).