Bug#917576: stegosuite: depends on libswt-gtk2 which is no longer built

[Jeremy Bicha]

Source: stegosuite
Version: 0.8.0-1
Severity: serious

jameica depends on libswt-gtk2-4-jni but that package is no longer
built by swt4-gtk.

Please switch to using libswt-gtk-4-jni instead (which uses gtk3
instead of gtk2).

Thanks,
Jeremy Bicha