This commit adds the following new variables:
horizon_requirements_git_repo
horizon_requirements_git_install_branch
When in developer mode, This repo is then cloned in horizon_install.yml
and used as an upper constraint in the functional test to avoid us
installing and running into issues resulting from uncapped dependencies
being installed.
This commit also changes the pip_install_options fact name in
horizon_install.yml to pip_install_options_fact. This allows us to
maintain the existing pip_install_options variable without overwriting
it with options when in developer mode, which ultimately means we can
have multiple services running in a container use a combination of
*_developer_mode: true and *_developer_mode: false. At the moment,
if a service writes pip_install_options fact with the constraints
options, those options will persist to other services running in the
container even if *_developer_mode: false.
Change-Id: If481de123073e46825cd5816062f08332d2d98fb
e672a26592