Add enh-ruby-mode expansions

Overrides mark-defun, as enh-ruby-mode has its own.
Merge pull request #108 from bradleywright/enh-ruby-mode

Add enh-ruby-mode expansions
Autoload enh-ruby-mode-expansions

This was missed in f1b0455db0aede8119fc4550f9bf3f2182a2bd37.

Also requires reindenting everything. Sorry.
Merge pull request #109 from bradleywright/enh-ruby-mode

Autoload enh-ruby-mode-expansions
Added missing 'provide' to enh-ruby-mode-expansions
Merge pull request #110 from jcinnamond/missing-provide

Added missing 'provide' to enh-ruby-mode-expansions