[arch-dev-public] [signoff] glib2 2.12.3-1

As brought up during discussions several times, glib2 has been moved to core as it is a makedepend for syslog-ng. Together with the move I updated this one to 2.12.3, which fixes some warnings, updates some documentation which we delete anyways, updates some translations and fixes a memleak. Please signoff for both architectures.