Rework docker script to allow to build packages as well

Move `tests/helpers/run-in-docker` to `packaging/run-in-docker` and add
package option to build gbp packages in a docker container.

1 files changed, 3 insertions, 2 deletions

diff --git a/HACKING b/HACKING
index 69a30961..877d73c7 100644
--- a/HACKING
+++ b/HACKING
@@ -17,8 +17,9 @@ other tests use:
 
     make all+net
 
-You can run the tests in a debian/sid docker container by using
-tests/helpers/run-in-docker.
+You can run the tests in a `debian:sid` docker container by using
+
+    packaging/run-in-docker
 
 Building the API Docs
 ---------------------