Update to 4.7.8. From the changelog:

* explicitly close current IMAP mailbox when selecting a new one,
    so all servers expunge deleted mail. Thanks: Josh Triplett.

* include experimental spec file for creating RPM with rpmbuild.
    Thanks: Dag Wieers, Rob Loos, Dries Verachtert.

* convert changelog to utf-8 encoding.

* update email addresses, etc. Domain for mailing lists has changed
    to lists.pyropus.ca.

* add FAQ about memory errors on OS X. Thanks: Andres Gasson.

* drop log message level for stderr output of destination if
    ignore_stderr is set, just like for filter. Thanks: Jeremy
    Chadwick.

(schmonz)