I think soon we'll put the Python 3 venv at `/srv/zulip-venv` and
make `/srv/zulip-py3-venv` just an alias to that (then remove the
alias too), but for now the old name is helpful for spotting places
that need an update.
The `/srv/zulip-venv` name still appears in codepaths used by Travis
tests.
The commit is composed of: (1) distill out top-level dependencies in
common.txt, (2) add -e flag to the vcs-based packages because
pip-compile can't do without, (3) pip-compile/generate the locked files
then remove the -e flags from the lockfile, (4) pin pathlib2 to dev.txt
because it turns out it is a direct requirement of
documentation_crawler, (5) document the structure and add an automation
script (6) remove cryptography==1.9 from requirements/scrapy.txt since
cryptography is automatically added from pyopenssl (7) add sed command
to remove future/futures from the generated lock file in python3 (this
should have been automatically handled by pip-compile, so pending for
the feature from pip-compile)
Tweaked by tabbott to update PROVISION_VERSION and add a missing
`first` dependency.
Greg Price
rht