fix apache-fast-test for use in eqiad

it wants to read the pybal configs from
somewhere. but in eqiad there is no /home/w/

so we need to replace it with something,
on tin would be nice, because we deploy from
here

can pybal config live in /srv ? i say that
because there is currently:

root@tin:/srv# ls
deployment  redis  scap

Change-Id: I5f05b9a5bdd5e1869f139900b0844cb52421de76