[feature/twig] INCLUDEJS behavior now supports local relative paths

This was done because T_TEMPLATE_PATH is not always correct for js files
(e.g. the inheriting style does not include these). Now we use the Twig
Loader to find the correct file to link to (most specific file first, then
parent styles). Also allows using @namespace convention

PHPBB3-11598

phpBB/styles/subsilver2/template/timezone_option.html

@@ -15,6 +15,6 @@
 			{S_TZ_OPTIONS}
 		</select>
 
-		<!-- INCLUDEJS {T_TEMPLATE_PATH}/timezone.js -->
+		<!-- INCLUDEJS timezone.js -->
 	</td>
 </tr>

phpBB/styles/subsilver2/template/ucp_groups_manage.html

@@ -95,7 +95,7 @@
 	</tr>
 	</table>
 
-<!-- INCLUDEJS {T_TEMPLATE_PATH}/avatars.js -->
+<!-- INCLUDEJS avatars.js -->
 
 <!-- ELSEIF S_LIST -->
 

phpBB/styles/subsilver2/template/ucp_profile_avatar.html

@@ -48,6 +48,6 @@
 	</tr>
 </table>
 
-<!-- INCLUDEJS {T_TEMPLATE_PATH}/avatars.js -->
+<!-- INCLUDEJS avatars.js -->
 
 <!-- INCLUDE ucp_footer.html -->