This update for gimp fixes the following issues:

- Don't build gimp with webkit1 support, as it is no longer maintained and has
plenty of security bugs.

This disables the GIMP's built-in help browser; it will use an external browser when configured this way.

This works around a number of security vulnerabilities in Webkit1.

This update was imported from the SUSE:SLE-12-SP2:Update update project.