Merge pull request #373 from gregors/bugs/fix_docs_to_use_valid_repo_name

update docs to use correct repo

Author: jbodah

README.md

@@ -30,11 +30,11 @@ each plugin. In general, you have to add a line to your `~/.vimrc`:
 
 ```viml
 " vim-plug
-Plug 'elixir-lang/vim-elixir'
+Plug 'elixir-editors/vim-elixir'
 " NeoBundle
-NeoBundle 'elixir-lang/vim-elixir'
+NeoBundle 'elixir-editors/vim-elixir'
 " Vundle
-Plugin 'elixir-lang/vim-elixir'
+Plugin 'elixir-editors/vim-elixir'
 ```
 
 ### Manual installation