Added online help content for MailHost.

lib/python/Products/MailHost/help/Mail-Host.dtml

+<dtml-var standard_html_header>
+<h1>Mail Host</h1>
+<p> Mail Hosts allow you to send mail via SMTP.</p>
+<dtml-var standard_html_footer>

lib/python/Products/MailHost/help/Mail-Host_Add.dtml

+<dtml-var standard_html_header>
+<h1>
+<a href="../Mail-Host.dtml">Mail Host</a>&gt;Add</h1>
+<p> This view allows you to create a new Mail Host.</p>
+<p> The <tt>Id</tt> field specifies the id of the mail host.
+		  The <tt>Title</tt> field allows you to specify the title of the mail
+		  host. The <tt>Local host</tt> field allows you to specify the name of
+		  the server on which Zope is running. The <tt>SMTP host</tt> field
+		  allows you to specify the name of the mail server. The <tt>SMTP
+		  port</tt> field allows you to specify the port on which the mail server
+		  accepts SMTP requests. The <tt>Max. timeout</tt> field allows you to
+		  specify how long Zope should wait (in seconds) for a response from the mail
+		  server before aborting a mail request. Click the <tt>Add</tt> button
+		  to create a new Mail Host.</p>
+<dtml-var standard_html_footer>

lib/python/Products/MailHost/help/Mail-Host_Edit.dtml

+<dtml-var standard_html_header>
+<h1>
+<a href="../Mail-Host.dtml">Mail Host</a>&gt;Edit</h1>
+<p> This view allows you to manage the attributes of the mail host.
+		  </p>
+<p> A mail host allows Zope to send mail with the SMTP protocol.
+		  </p>
+<p> The <tt>Id</tt> field indicates the id of the mail host.
+		  The <tt>Title</tt> field allows you to specify the title of the mail
+		  host. The <tt>Local host</tt> field allows you to specify the name of
+		  the server on which Zope is running. The <tt>SMTP host</tt> field
+		  allows you to specify the name of the mail server. The <tt>SMTP
+		  port</tt> field allows you to specify the port on which the mail server
+		  accepts SMTP requests. The <tt>Max. timeout</tt> field allows you to
+		  specify how long Zope should wait (in seconds) for a response from the mail
+		  server before aborting a mail request. </p>
+<dtml-var standard_html_footer>

lib/python/Products/MailHost/help/Mail-Host_Security.dtml

+<dtml-var standard_html_header>
+<h1>
+<a href="../Mail-Host.dtml">Mail Host</a>&gt;Security</h1>
+<p> See <a href="../Folder_Security.dtml">Folder&gt;Security</a>. </p>
+<dtml-var standard_html_footer>