dag: Focus the graph view on startup

Make the navigation shortcuts available by focusing the graph
widget after the history is loaded.

Signed-off-by: David Aguilar <davvid@gmail.com>

cola/dag/view.py

@@ -722,6 +722,7 @@ def add_commits(self, commits):
 
     def thread_done(self):
         self.setEnabled(True)
+        self.graphview.setFocus()
         try:
             commit_obj = self.commit_list[-1]
         except IndexError: