remove git submodules
Squashed 'independent/vim/bundle/vim-rails/' content from commit bdc3238

git-subtree-dir: independent/vim/bundle/vim-rails
git-subtree-split: bdc32389e7053c608a65f870c6c8f5e1210432a7
Merge commit '0ed670c991daf563236d5cced5fa82936e264402' as 'independent/vim/bundle/vim-rails'
Squashed 'independent/vim/bundle/vim-rvm/' content from commit 9ffa92f

git-subtree-dir: independent/vim/bundle/vim-rvm
git-subtree-split: 9ffa92fe903c12defefb3b5ec714de825f322bf2
Merge commit '77468e4a719c62e33b3469946187ea6efd316a86' as 'independent/vim/bundle/vim-rvm'
Squashed 'independent/vim/bundle/vim-ps1/' content from commit 2c241d1

git-subtree-dir: independent/vim/bundle/vim-ps1
git-subtree-split: 2c241d1360c8f7711fbba22afbb6a96e1ebcc2b2
Merge commit '1f12a018b939b51e39ac3424b04db798d1677e4b' as 'independent/vim/bundle/vim-ps1'
Squashed 'powershell/Modules/posh-git/' content from commit 22f4e77

git-subtree-dir: powershell/Modules/posh-git
git-subtree-split: 22f4e7715e1e117547e5dec1ee6c2b8dccaeb2e8
Merge commit '451ae9cbbd8bd9399d22b4dac769be976e3c81ed' as 'powershell/Modules/posh-git'
Squashed 'powershell/Modules/posh-svn/' content from commit a862b1f

git-subtree-dir: powershell/Modules/posh-svn
git-subtree-split: a862b1f3d2a4cd264a60963abe8c0bed895b2484
Merge commit '15e403cbef28ebb1ec998b2551d258ccfe479de8' as 'powershell/Modules/posh-svn'
Add instructions for update subtrees
Make commands readable
Move subtree content to Readme.md