project: override log domains

This way, we can have more useful debug spils.

src/gcal-subscriber-view.c

@@ -18,6 +18,8 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
+#define G_LOG_DOMAIN "GcalSubscriberView"
+
 #include "gcal-subscriber-view.h"
 #include "gcal-subscriber-view-private.h"