Fix duplicated 'Firewall Settings' string on Startup tab bnc#884058

Seems there is an unecessary Frame with extra title (the title is the
repeated text) here (which encloses the custom FIREWALL widget).The
FIREWALL widget on its own already contains the text that is repeated.
Merge pull request #20 from noelpower/fix-repeated-string

Fix duplicated 'Firewall Settings' string on Startup tab bnc#884058