docs: remove exploring sdk link

  <ul>

    <li>Create, delete, and view Android Virtual Devices (AVDs). See <a href=

    "{@docRoot}tools/devices/managing-avds-cmdline.html">Managing AVDs from the Command

Line</a>.</li>

    "{@docRoot}tools/devices/managing-avds-cmdline.html">Managing AVDs from the Command Line</a>.</li>

    <li>Create and update Android projects. See <a href=

    "{@docRoot}tools/projects/projects-cmdline.html">Managing Projects from

    the Command Line</a>.</li>

    <li>Update your Android SDK with new platforms, add-ons, and documentation. See <a href=

    "{@docRoot}sdk/exploring.html">Exploring the SDK</a>.</li>

  </ul>If you are using Eclipse, the <code>android</code> tool's features are integrated

  into ADT, so you should not need to use this tool directly.

    "{@docRoot}tools/help/sdk-manager.html">SDK Manager</a>.</li>

  </ul>

<p>If you are using Android Studio or Eclipse, the <code>android</code> tool's features are

integrated into the IDE, so you should not need to use this tool directly. </p>

  <p class="note"><strong>Note:</strong> The documentation of options below is not exhaustive

and may be out of date. For the most current list of options, execute <code>android