title: .gitignore is ignoring other directories with the same name
body: <p>I have a problem in my .gitignore. 
  I want it to just ignore the 'vendor/' directory, but it is ignoring all directories with that name.</p>
  
  <p>Below is my .gitignore: </p>
  
  <pre><code>.idea/ 
  bin/ 
  vendor/ 
  composer.lock 
  composer.phar 
  </code></pre>
  
  <p>Below is the result of my 'git status': </p>
  
  <pre><code>Changes not staged for commit: 
     (use "git add &lt;file&gt; ..." to update what will be submitted) 
     (use "git checkout - &lt;file&gt; ..." to discard changes in working directory) 
  
  modified: .gitignore 
  
  Not monitored files: 
     (use "git add &lt;file&gt; ..." to include what will be submitted) 
  
  src/vendor/ 
  tests/src/ 
  vendor/ 
  </code></pre>
  
  <p>It is also ignoring 'src/vendor', I do not want that to happen, I want it to ignore 'vendor/'</p>