Plugin Installation and Version Management is done via git submodules. Plugins are loaded via tpope's vim-pathogen.
cd ~/.dotfiles
git submodule add <url-to-plugin.git> dotdirs/.vim/bundle/<plugin-name.git>
set PLUGIN_NAME "plugin.git"
git submodule deinit -f -- dotdirs/.vim/bundle/${PLUGIN_NAME}
rm -rf .git/modules/dotdirs/.vim/bundle/${PLUGIN_NAME}
git rm -f dotdirs/.vim/bundle/${PLUGIN_NAME}
cd ~/.dotfiles
git submodule update --recursive --remote