cherry-pick: docs: Added note that <application> at end of manifest.

<code><a href="{@docRoot}guide/topics/manifest/activity-element.html">&lt;activity&gt;</a></code>,

<code><a href="{@docRoot}guide/topics/manifest/provider-element.html">&lt;provider&gt;</a></code>, and

<code><a href="{@docRoot}guide/topics/manifest/service-element.html">&lt;service&gt;</a></code>

elements can be intermixed in any sequence.  (An 

<code><a href="{@docRoot}guide/topics/manifest/activity-alias-element.html">&lt;activity-alias&gt;</a></code>

element is the exception to this rule:  It must follow the 

elements can be intermixed in any sequence. There are two key exceptions to this

rule, however:

<ul>

  <li>

    An <code><a href="{@docRoot}guide/topics/manifest/activity-alias-element.html">&lt;activity-alias&gt;</a></code>

    element must follow the

    <code><a href="{@docRoot}guide/topics/manifest/activity-element.html">&lt;activity&gt;</a></code>

it is an alias for.)

    it is an alias for.

  </li>

  <li>

    The <code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code>

    element must be the last element inside the

    <code><a href="{@docRoot}guide/topics/manifest/manifest-element.html">&lt;manifest&gt;</a></code>

    element. In other words, the <code>&lt;/application&gt;</code> closing tag

    must appear immediately before the <code>&lt;/manifest&gt;</code> closing

    tag.

  </li>

</p></dd>

<dt><b>Attributes</b></dt>