port to drupal 5.x

I try adsense_injector with drupal5 and with some minor changes, it seems work correctly... but there's no setting page, so it works only if already configured with drupal4.7 and then upgraded to drupal5.
I attach the .module file modified. Also, it needs an .info file (you could copy other info file from modules already converted to work with drupal-5. I hope it could be useful.

Checked in CVS: http://drupal.org/cvs?commit=53021

I'll create a drupal 5 package. Please wait for the release system to build it.