Begin building virtualenvs for each component

To get this to work you'll need to install the following before running:

sudo yum install libxslt-devel libxml2-devel mysql-devel \
                 postgresql-devel openldap-devel psmisc \
                 sqlite-devel libvirt-devel

To have anvil build virtualenv apply the jsonpatch file anvil includes
in conf/distros to the distro file using the --distros-patch option.

sudo ./smithy --action=prepare --distros-patch=conf/distros/venv-patch.json

A separate virtualenv will be built for every component listed in
personas file.  Requirements will not be shared across virtualenv.

o add --venv-deploy-dir option to make the virtualenv relocatable
  to a path different from the build path
o add --origins-patch to apply the jsonpatch file anvil includes
  in conf/origins to the origins file in order to skip bundling
  test requirements into the virtualenv

Change-Id: I47fdb68e71c3114f9cf441b3b33be9c7591356aa
Merge "Begin building virtualenvs for each component"