Fix formatting of changelog trailing line dates.

debian/changelog

@@ -2,31 +2,31 @@ openstreetmap-cgimap (0.5.0-0ubuntu2ppa1~xenial5) xenial; urgency=medium
 
   * Bump version to get launchpad to build it.
 
- -- Matt Amos <zerebubuth@gmail.com>  Mon  3 Oct 2016 11:30:02 +0100
+ -- Matt Amos <zerebubuth@gmail.com>  Mon, 3 Oct 2016 11:30:02 +0100
 
 openstreetmap-cgimap (0.5.0-0ubuntu2ppa1~xenial4) xenial; urgency=medium
 
   * Bump version to get launchpad to build it.
 
- -- Matt Amos <zerebubuth@gmail.com>  Mon  3 Oct 2016 10:56:02 +0100
+ -- Matt Amos <zerebubuth@gmail.com>  Mon, 3 Oct 2016 10:56:02 +0100
 
 openstreetmap-cgimap (0.5.0-0ubuntu2ppa1~xenial3) xenial; urgency=medium
 
   * Bump version to get launchpad to build it.
 
- -- Matt Amos <zerebubuth@gmail.com>  Mon  3 Oct 2016 10:37:45 +0100
+ -- Matt Amos <zerebubuth@gmail.com>  Mon, 3 Oct 2016 10:37:45 +0100
 
 openstreetmap-cgimap (0.5.0-0ubuntu2ppa1~xenial2) xenial; urgency=medium
 
   * Bump version to get launchpad to build it.
 
- -- Matt Amos <zerebubuth@gmail.com>  Sun 25 Sep 2016 11:43:44 +0100
+ -- Matt Amos <zerebubuth@gmail.com>  Sun, 25 Sep 2016 11:43:44 +0100
 
 openstreetmap-cgimap (0.5.0-0ubuntu2ppa1~xenial1) xenial; urgency=medium
 
   * Add support for changeset metadata and discussions.
 
- -- Matt Amos <zerebubuth@gmail.com>  Mon 19 Sep 2016 21:07:06 +0100
+ -- Matt Amos <zerebubuth@gmail.com>  Mon, 19 Sep 2016 21:07:06 +0100
 
 openstreetmap-cgimap (0.4.3-0ubuntu2ppa1~xenial2) xenial; urgency=medium