Installation:

    cd ~
    git clone git://github.com/gutoyr/dotvim.git ~/.vim
    #ln -s ~/.vim/vimrc ~/.vimrc
    #ln -s ~/.vim/gvimrc ~/.gvimrc
    cd ~/.vim
    git submodule init
    git submodule update

Upgrading a plugin bundle:

    cd ~/.vim/bundle/fugitive
    git pull origin master

Upgrading all bundled plugins:

    git submodule foreach git pull origin master

Adding a plugin bundle:

    cd ~/.vim
    git submodule add http://github.com/tpope/vim-fugitive.git bundle/fugitive
    git add .
    git commit -m "Install Fugitive.vim bundle as a submodule."

git submodule + pathogen reference

Removing a plugin bundle:

    cd ~/.vim
    git submodule deinit -f bundle/fugitive
    git rm bundle/fugitive
    git clean -dfx

or

To remove a submodule you need to:

Delete the relevant section from the .gitmodules file.
Stage the .gitmodules changes git add .gitmodules
Delete the relevant section from .git/config.
Run `git rm --cached path_to_submodule` (no trailing slash).
Run `rm -rf .git/modules/path_to_submodule`
Commit `git commit -m "Removed submodule <name>"`
Delete the now untracked submodule files
`rm -rf path_to_submodule`

git submodule reference