Restore "hub" support using g:fugitive_git_command

README.markdown

@@ -6,6 +6,9 @@ of features:
 * Enables `:Gbrowse` from fugitive.vim to open GitHub URLs.  (`:Gbrowse`
   currently has native support for this, but it is slated to be removed.)
 
+* Sets up `:Git` to use [`hub`](https://github.com/github/hub) if installed
+  rather than `git`.
+
 * In commit messages, GitHub issues, issue URLs, and collaborators can be
   omni-completed (`<C-X><C-O>`, see `:help compl-omni`).  This makes inserting
   those `Closes #123` remarks slightly easier than copying and pasting from

plugin/rhubarb.vim

@@ -11,6 +11,10 @@ if !exists('g:dispatch_compilers')
 endif
 let g:dispatch_compilers['hub'] = 'git'
 
+if get(g:, 'fugitive_git_command', 'git') ==# 'git' && executable('hub')
+  let g:fugitive_git_command = 'hub'
+endif
+
 function! s:config() abort
   let common_dir = fugitive#buffer().repo().dir('commondir')
   if filereadable(common_dir)