~/.vimrc: Add tern.js.

It's quite cool, although I've yet to use it. Maybe some spring cleaning
is coming?

.vimrc

@@ -22,6 +22,8 @@ if isdirectory($HOME . '/.vim/bundle/vundle')
	Bundle 'airblade/vim-gitgutter'
	highlight SignColumn ctermbg=0
	Bundle 'terryma/vim-multiple-cursors'
	Bundle 'marijnh/tern_for_vim'
endif
" Have syntax highlighting and non-vi features