Added a .irssi config directory and fixed bug in vimrc

There was some issue with the placement of the colorschem in my vimrc
file, plain text files (and some others) were not getting
highlighted. I think it is related to the syntax reset statement in
the hipster.vim colorscheme. Moving the colorscheme to the end of the
.vimrc corrects it for the moment.

Signed-off-by: Ian Allison <iana@pims.math.ca>