title: regex - Match filename with or without extension
body: <p>Need a regex pattern to match all of the following:</p>
  
  <pre><code>hello
  hello.
  hello.cc
  </code></pre>
  
  <p>I tried <code>\b\w+\.?\w+?\b</code>, but this doesn't match <code>"hello."</code> (the second string mentioned above).</p>