Updated forum to html5 compliance and validated

I have Updated forum to html5 compliance and validated.  Added some css to the files and changed some tags.  All added to the forum style.css file.  You mentioned that you wanted to get away from the master css file for the plugins.  This is a start of that process.  No tags were removed from the theme's css file.  The admin pages were not changed or updated.  There was one issue with the name= needing to be changed to an id=  Other than that, looks good.