+Provide 'G' key binding to trigger mail refresh
+
+ The 'G' key works wherever '=' works. Before refreshing the screen
+ it calls an external program that can be used to poll email servers,
+ run notmuch new and setup specific tags for the new emails. The
+ script to be called can be customized with. Use the customize screen
+ to set the notmuch-poll-script variable to the program that you want
+ to execute when pressing 'G'. Note that this is synchronous - emacs
+ will wait until this program finishes.
+