Ensure Zulip virtualenvs are world-readable.

This is important for both ensuring the Nagios checks work correctly
in production, as well as making sure the `zulip` user can access the
virtualenv (owned by the `travis` user) in Travis CI.

scripts/lib/setup_venv.py

@@ -68,3 +68,4 @@ def do_setup_virtualenv(venv_path, requirements_file, virtualenv_args):
 
     run(["pip", "install", "--upgrade", "pip"])
     run(["pip", "install", "--no-deps", "--requirement", requirements_file])
+    run(["sudo", "chmod", "-R", "a+rX", venv_path])

tools/travis/setup-production

@@ -2,6 +2,10 @@
 set -e
 set -x
 
+# Make /home/travis world-readable so the `zulip` user will be able to
+# read it.
+sudo chmod a+rX /home/travis
+
 # Uninstall the unnecessary extra versions of postgres that Travis CI
 # installs since if we don't do this, doing apt upgrades can fail due
 # to conflicts over which version of postgres should be running.