Misleading error message when running on old GTK (less than 3.20)

Created by: laksono

When running hpcviewer on Linux with older GTK (less than GTK 3.20) the error message is misleading. Need to check and have a better error message.

The output of hpcviewer in the terminal has a better error message:

***WARNING: GTK+ version too old (micro mismatch)
***WARNING: SWT requires GTK 3.20.0
***WARNING: Detected: 3.14.13

See SWT code at https://github.com/eclipse/eclipse.platform.swt/blob/6fd83193fd4910702e60fa142a923056bbaf1ca2/bundles/org.eclipse.swt/Eclipse%20SWT/gtk/org/eclipse/swt/widgets/Display.java#L1145