Mark Tails 2.10~rc1 as released.

debian/changelog

-tails (2.10~rc1) UNRELEASED; urgency=medium
+tails (2.10~rc1) unstable; urgency=medium
 
   * Major new features and changes
     - Upgrade the Linux kernel to 4.8.0-0.bpo.2 (Closes: #11886).
@@ -109,7 +109,7 @@ tails (2.10~rc1) UNRELEASED; urgency=medium
     - Allow connections to Tor's control port during stream isolation
       tests, but only for those applications where we expect that.
 
- -- Tails Developers <tails@boum.org>  Thu, 12 Jan 2017 20:27:43 +0100
+ -- Tails Developers <tails@boum.org>  Thu, 12 Jan 2017 23:50:39 +0100
 
 tails (2.9.1) unstable; urgency=medium