Accessibility of floated table - enhancement

First of all I don't have a complete understanding of everything I did in this pull request.  So definitely want to be careful when looking at/pulling this.  But essentially what is needed is the floated head removes the thead from the original table and puts it in a new table.  Then some column spacers are put in the original headers place.  It would be helpful to visually impaired folks if we were able to stick the original th text back in there so that as they are reading through the body of the table they will be able to tell which column they are on.

I didn't do this but it may also be nice to add some sort of table caption to the added table indicating it is only used for non-visually impaired.

but otherwise this plugin is awesome!!