Introducing more Drupal goodness in the code

I made different improvements to the code replacing the verbose definitions of JS arrays with calls to drupal_js.
As a bonus I implemented long versions of day and months.
Tested on Drupal 6.
Minor fixes and other additions:
- indentation and variable naming ($out becomes $output, that is more Drupal-style)
- in the theme function td's to have classes and not id's, id's should be unique and they weren't (the other way round would be to give them unique id's as you are doing with worlclock)
- changed theme function to accept $timestr as a parameter, hence giving the change of printing the date() in case JS is disabled (addressing #256624)
- added support for n and W (DOW (1 - 7) ISO-8601 or (0 - 6))

By the way, as per Drupal guidelines http://drupal.org/handbook/cvs/quickstart#commit and http://drupal.org/node/52287, I'd be grateful if you mentioned my nickname on the commit messages.