title: Typedoc throws error with a node_modules package.json
body: <p>I'm pretty new using Typedoc and I have troubles with a thrown error.</p>
  
  <p>When I run Typedoc in my project, the doc is correctly generated but I also get an error:</p>
  
  <p><code>$ ./node_modules/.bin/typedoc --mode file --module commonjs --out ./docs/typescript --target es5 src/
  Error: Could not parse /home/michael/workspace/test/node_modules/paralleljs/package.json
  </code></p>
  
  <p>I don't understand why Typedoc looks into node_modules/ while I specified to generate the docs on src/ (both are at the same level).</p>
  
  <p>I also tried to exclude <code>node_modules</code> with <code>--exclude "**/node_modules/**/*"</code> or <code>--externalPattern "**/node_modules/**/*"</code> but it seems to do nothing.</p>
  
  <p>If someone could help / explain me why it is behaving like that, i would be grateful to him/her.</p>