In venv --upgrade does nothing good since venv have constraints-bound
versions of everything installed. It does bad thing though: it tries to
upgrade setuptools (they are not mentioned in upstream constraints.txt)
and break further building.
Change-Id: I1abab5f51ab81faf11c19c569fa74f57202963fb
--no-cache-dir is now default for microservices venv and there's no need
to pass requirements.txt to pip directly, especially as constraints
file.
Change-Id: Id100bd1972d00353ca93ecbc04c4f1843fe089bf
Images will be built with sources from master branch of
https://github.com/openstack/heat.git repository by default.
Change-Id: Ib6d5873b107760c025191b26bfcd1b99571f0fa5
Depends-On: I4d91aa8632fcd55735d791300fde475696b435b5