Add sdist make target to build the MANIFEST.in file.

Makefile

@@ -24,8 +24,17 @@ clean:
 clean-all: clean
 	rm -rf $(venv)
 
+MANIFEST.in:
+	[ -d .bzr ] || (echo "Must be a bzr checkout" ; exit 1)
+	bzr ls --kind=file -VR | while read f; do echo include "$$f"; done > $@
+
+sdist: MANIFEST.in
+	python setup.py sdist
+
 $(venv):
 	@echo "You need to install the Nova virtualenv before you can run this."
 	@echo ""
 	@echo "Please run tools/install_venv.py"
 	@exit 1
+
+.PHONY: MANIFEST.in