VIM JavaScript syntax updated to 0.6

We have been there 0.5.1 for some monthes. Today, we will move to 0.6 :) The mainly changed part is JSDoc introduction.

The syntax file has been downloaded by 1019, it's rating 256/77 at 2006-10-17.
It is the 4th rated syntax file at VIM site. Please vote me, if it is helpful :)

I hope it can come into the offical VIM package in the near later.