Add debian packaging

Adds debian packaging, including the vendored version of libjuju

Signed-off-by: Adam Israel <adam.israel@canonical.com>
diff --git a/Makefile b/Makefile
index 4655d33..c63a6ba 100644
--- a/Makefile
+++ b/Makefile
@@ -9,3 +9,5 @@
 	tox
 lint:
 	tox -e lint
+package:
+	python3 setup.py --command-packages=stdeb.command bdist_deb