* some changes

* moved some admin html code from php to twig templates (.html files)
* minimum PHP version required by installer is now 5.1.2, cause of spl_autoload_register functon.
* depracated Twig to version 1.20.0 cause of Autoloader
* removed unused admin stylish template

system/templates/admin.visitors.html

@@ -0,0 +1,19 @@
+Users being active within last {{ config_visitors_counter_ttl }} minutes.<br/><br/>
+<table class="table" width="100%" border="0">
+	<tr>
+		<th><b>IP</b></th>
+		<th><b>Last visit</b></th>
+		<th><b>Page</b></th>
+	</tr>
+{% set i = 0 %}
+{% for visitor in visitors %}
+	{% set i = i + 1 %}
+	<tr>
+		<td>{{ visitor.ip }}</td>
+		<td>{{ visitor.lastvisit|date("H:i:s") }}</td>
+		<td>
+			<a href="{{ visitor.page }}">{{ visitor.page|slice(0, 50) }}</a>
+		</td>
+	</tr>
+{% endfor %}
+</table>