Minor fix for url_for using hash params

Minor fix for url_for where additional values are (incorrectly) set in the hash...

Before fix:

options = {:controller => 'projects', :action => 'index'} url_for(options) options => {:controller => 'projects', :action => 'index', :host => 'www.example.com', :protocol => 'http'}

After fix:

options = {:controller => 'projects', :action => 'index'} url_for(options) options => {:controller => 'projects', :action => 'index'}

Pull request at:

Thanks, Andrew