[Gui] remove unused help button from preferences dialog

- is by default in the title bar of Qt dialogs, has to be removed explicitly when unused

- also fix too long code lines

src/Gui/Tree.cpp

@@ -3235,7 +3235,8 @@ void DocumentItem::slotInEdit(const Gui::ViewProviderDocumentObject& v)
 {
     (void)v;
 
-    ParameterGrp::handle hGrp = App::GetApplication().GetParameterGroupByPath("User parameter:BaseApp/Preferences/TreeView");
+    ParameterGrp::handle hGrp = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/TreeView");
     unsigned long col = hGrp->GetUnsigned("TreeEditColor", 4294902015);
     QColor color((col >> 24) & 0xff, (col >> 16) & 0xff, (col >> 8) & 0xff);