Commit 2d5b1aa9d1 removed the
GCAL_WINDOW_VIEW_DAY variant of the GcalWindowView enum. Since then, the
change-view accelerators to switch to GCAL_WINDOW_VIEW_{WEEK,MONTH,YEAR}
were broken, as the accelerator setup was assuming
GCAL_WINDOW_VIEW_WEEK==1, which isn't true anymore with
GCAL_WINDOW_VIEW_DAY being gone.
This change fixes the enum values in the accelerator setup.
