notmuch release 0.22 now available

[Franz Fellner]

On Tue, 26 Apr 2016 22:04:48 -0300, David Bremner <david at tethera.net> wrote:
> Xapian 1.3 support
> 
>   Notmuch should now build (and the test suite should pass) on recent
>   releases of Xapian 1.3.x. It has been tested with Xapian 1.3.5.

Great to see support for the most recent xapian releases. THX!

Just some questions:
Is it safe to just run the update?
Are some special steps required to update the DB to the new backend?