Update to the heat theme maps for words

The heattheme service has been updated to now show a set of scores for the submitted text.

It's also been reimplemented in perl, so it moves from .php to .cgi, but all existing inbound links will just work, and will continue to work.

I should especially thank Tim Yao for his fog tool for all the ideas behind these enhancements.

One remaining task is to add support for the missing bits of output which you get from GNU diction. Anyone happen to know of a perl module which does this?