Merge "Doc update: misc GCM fixes" into klp-docs

{@code dependency} section of your application's {@code build.gradle} file:</p>

<pre>dependencies {

   compile: "com.google.android.gms:play-services:3.1.+"

  compile "com.google.android.gms:play-services:3.1.+"

}

</pre>

 <li>Under <strong>Public API access</strong>, click <strong>Create new key</strong>.</li>

<li>In the <strong>Create a new key</strong> dialog, click <strong>Android key</strong>.</li>

<li>In the resulting configuration dialog, supply one SHA1 fingerprint and

the package name for your app, separated by a semicolon. For example,

{@code 45:B5:E4:6F:36:AD:0A:98:94:B4:02:66:2B:12:17:F2:56:26:A0:E0;com.myexample}.

<p>To get the value for the SHA1 fingerprint, follow the instructions in the

<a href="http://developers.google.com/console/help/new/#installedapplications">console

help</a>.</p></li>

<li>In the <strong>Create a new key</strong> dialog, click <strong>Server key</strong>.</li>

<li>In the resulting configuration dialog, supply your server's IP address. For testing

purposes, you can use {@code 0.0.0.0/0}.</p></li>

<li>Click <strong>Create</strong>.</li>

<li>In the refreshed page, copy the

<li>Write your client app. This is the GCM-enabled Android application that runs

on a device. See <a href="client.html">Implementing GCM Client</a> for more information.</li>

</ol>

  <li>Able to store the API key and client registration IDs. The

API key is included in the header of POST requests that send

messages.</li>

 <li>Able to store the API key and client registration IDs.</li>

 <li>Able to generate message IDs to uniquely identify each message it sends.</li>

</ul>