webadmin: adjusted radio label centering

Radio button labels were all off vertical center (low) by about
2 pixels. Fixed.

Bug-Url: https://bugzilla.redhat.com/1146141
Change-Id: Ib62f477312d0065479881e6bc7018dc5f4ea6762
Signed-off-by: Greg Sheremeta <gshereme@redhat.com>