Fixed "Add to library" button showing up for apps

Caused by one occurence of "uniboardtool" having been replaced by
"OpenboardTool" instead of "openboardtool".
For consistency's sake, this was changed to openboardtool, but these URL
/ application name changes require a clean-up (all occurences of
"uniboardtool" are commented out; these should either be removed, or the
changes reverted)

src/core/UBApplication.cpp

@@ -646,7 +646,7 @@ bool UBApplication::isFromWeb(QString url)
 {
     bool res = true;
 
-    if( url.startsWith("OpenboardTool://") ||
+    if( url.startsWith("openboardtool://") ||
         url.startsWith("file://") ||
         url.startsWith("/")){
         res = false;