* reverted removing base href in html head

* added anonymous usage statistics reporting
* (fix) don't show templates that doesn't exist in Menus option in Admin Panel
* (fix) menu ordering by category
* (fix) showing changelog with urls in Admin Panel
* (internal) moved uninstall logic to Plugins class

system/templates/install.config.html.twig

@@ -31,6 +31,18 @@
 				<em>{{ locale.step_config_client_desc }}</em>
 			</td>
 		</tr>
+		<tr>
+			<td>
+				<label for="vars_usage">
+					<span>{{ locale.step_config_usage }}</span>
+				</label>
+				<br>
+				<input type="checkbox" name="vars[usage]" id="vars_usage" value="1" checked/>
+			</td>
+			<td>
+				<em>{{ locale.step_config_usage_desc }}</em>
+			</td>
+		</tr>
 	</table>
 
 	{{ buttons|raw }}