Add submodule vim-powerline
Comment-out the call to depricated Pl#load()
Remove submodule vim/bundle/vim-powerline
I acquiesce to the new vision of Powerline as a system-wide package
Augment runtimepath in vimrc for submodule vim/bundle/vim-powerline
Add submodule vim/bundle/vim-powerline
Add submodule vim/bundle/vim-airline to replace powerline