title: Cannot use remote repository in a composer on windows
body: <p>I have a repository with library. It could be successfully cloned.</p>
  
  <pre><code>$ git clone file:////remote/repo/library
  $ cd library
  $ composer validate
  ./composer.json is valid, but with a few warnings
  </code></pre>
  
  <p>But it seems that this repostory cannot be used via a composer inclusion.</p>
  
  <pre><code>...
  "repositories": [
      {
          "type": "git",
          "url": "file:////remote/repo/library"
      }]
   ...
  </code></pre>
  
  <p>Trying to install</p>
  
  <pre><code>$ composer install -vvv
  ... 
  Loading composer repositories with package information
  Executing command (//remote/repo/library): git show-ref --tags
  Executing command (//remote/repo/library): git branch --no-color --no-abbrev -v
  Executing command (//remote/repo/library): git branch --no-color
  Executing command (//remote/repo/library): git show "master":composer.json
  
    [Composer\Repository\InvalidRepositoryException]
    No valid composer.json was found in any branch or tag of 
    file:////remote/repo/library, could not load a package from it.
  ...
  </code></pre>
  
  <p>How to use a remote repository on windows with a composer?</p>