exVim Update to 8.04

[Wu Jie]

exVim 8.04 is released !

You can download it from:

http://code.google.com/p/exvim/downloads/list

Also available in:

http://www.ex-dev.com/en/tools/exvim/downloads/

If you are upgrade from exVim 8.03, please note that the
_vimfiles_your_project now turn to .vimfiles.your_project.
You may need to re-update all your exists project (use :Up), if you
are lazy, rename _vimfiles_your_project to .vimfiles.your_project
would be a faster way (Not test if it works fine).