system-config-printer: Two fixes

This update fixes the following issues with system-config-printers:
- bnc#852450: Require GTK 3.0 typelibs
- bnc#852842: Require system-config-printer from -applet instead of system-config-printer-common

Fixed bugs
bnc#852450
system-config-printer fails on start
bnc#852842
system-config-printer-applet makes unexpected setup to print to a remote CUPS queue
Selected Binaries
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