Because the swift functests (which use test.conf) run out of a
virtualenv they don't get access to the system wide trust of the
devstack CA. Handle this by explicitly configuring the cafile to trust
in the test.conf file.
We also set the web_front_end to apache2 as that is what is terminating
TLS for us. The tests handle different web server behaviors using this
flag.
Swift's functests will need to read these values in and properly
configure things on its end.
Change-Id: I4cdba36ccab6acd76205184882ee29e4f1e12333
e28db4c2f2