MDL-37023 JavaScript: Correct parsing of block regions

Where a block region consisted of multiple hyphen-separated words, the dock
code was unable to correctly rewrite the name of the class, causing the
layout to be incorrect.

Original patch provided by Mark Nielsen with changes by Andrew Nicols.

Committer: Andrew Nicols <andrew@nicols.co.uk>
MDL-37023 JavaScript: The dock should only handle pre and post blocks

Original patch provided by Mark Nielsen with changes by Andrew Nicols.

Committer: Andrew Nicols <andrew@nicols.co.uk>