Added the awesome patch to Ramaze::Cache::Sequel added by Lars Olsson…

…. While I cleaned up

most of the code so that it meets the standards of Ramaze it could be that I missed 
something so it would be cool if @manveru could take a better look at it.

An example of using the new Sequel cache works like the following:

Ramaze.options.cache.session = Ramaze::Cache::Sequel.using(
  :connection => Sequel.mysql(
    :host     => 'localhost', 
    :user     => 'user',
    :password => 'password', 
    :database => 'blog'
  ),
  :table => :blog_sessions
)

For more information on this patch read the following thread on the mailing list: 
https://groups.google.com/d/topic/ramaze/kWO8u5NrA-c/discussion