Leverage upper-constraints files to pin all dependencies

Leverage upper-constraints files to pin all dependencies

It leverages the latest change from lfdocs-conf and the
upper-constraints.txt now centralized in ONAP docs.
In a long run, upperconstraints.os.txt should be removed once ONAP
is synced with OpenStack.

It removes tox and setuptools from requirements as nothing depends on them
(most requirements should be removed except lfdocsconf)

Issue-ID: DOC-765

Signed-off-by: Andreas Geissler <andreas-geissler@telekom.de>
Change-Id: I0e017b8ffaeaa6626d3196b6442f87a500263457
(cherry picked from commit 995fa60569d369153b6829ca607e87159338d657)