Creates a separate DispatchType for Regex/Regexp/LocalRegex/LocalRegexp

- Reduces the special purpose code in the core Catalyst::Dispatcher by
  splitting the functionality previously handled by Regex into Regex,
  Regexp, LocalRegex and LocalRegexp. This removes all the code
  dedicated to Regex in Catalyst::Dispatcher, with the exception of
  depreciation warnings.
- Minimizes complexity in this distribution by making the new modules
  mostly subclasses of Regex.
- Dispatch order is no longer guaranteed to be Regex before LocalRegex
  (was it ever?). It now depends on when the DispatchType is seen in a
  controller.
- Improves the documentation.