Added software_installed.php

This is a HTML include file which presents information to the if the
installer finds an existing database file.
- helps to separate logic (php) from presentation (HTML)

setup/software_installed.php

@@ -0,0 +1,11 @@
+<?php if( !isset($xot_setup) ) { die( 'Access denied.'); } ?>
+    <h2>Software Installed</h2>
+
+    <p>Xerte Online Toolkits appears to be installed.</p>
+    <p>To go to your installation visit: <a href="<?php echo $xot_setup->xot_url; ?>" title="<?php echo $xot_setup->xot_url; ?>"><?php echo $xot_setup->xot_url; ?></a>.</p>
+
+    <h3>To reinstall:</h3>
+
+    <ul>
+        <li>Delete 'database.php' from <code><?php echo $xot_setup->root_path; ?></code></li>
+    </ul>