ui: added help texts to directory list boxes

* added a ? button to the labels of the directory list boxes to show help messages
* added a window stack to QtMainWindow for easier screen handling
* added a button to the preferences in the project setup
* removed 'has seen settings' flag from AppSettings

bin/app/data/ApplicationSettings_template.xml

@@ -40,13 +40,11 @@
 	</code>
 
 	<user>
-		<has_seen_settings><!-- BOOL: if the user was already asked to enter app settings --></has_seen_settings>
-
 		<recent_projects>
 			<recent_project><!-- STRING: recent project path --></recent_project>
 		</recent_projects>
 	</user>
-	
+
 	<network>
 		<plugin_port><!-- INTEGER: port the plugin listens to, standard is 6666 --></plugin_port>
 		<coati_port><!-- INTEGER: port coati is listening to, standard is 6667 --></coati_port>

bin/app/data/gui/setting_window/window.css

@@ -31,6 +31,20 @@ QLineEdit:disabled {
 	font-weight: bold;
 }
 
+#form #help {
+	background: transparent;
+	border: 1px solid #575656;
+	border-radius: 9px;
+	color: #575656;
+	height: 16px;
+	width: 16px;
+}
+
+#form #help:hover {
+	border-color: black;
+	color: black;
+}
+
 #moreButton {
 	background-color: rgba(255, 255, 255, 200);
 	border: 1px solid lightgray;