remove multi-host timeout

If you ran exercises with MULTI_HOST enabled, an additional sleep was
performed. This change removes that sleep to speed up tests.

Change-Id: I9dfd61cbb9415bd5e8fd1e40f4e41512be2ae0d2
xenapi: Increase default OS domU memory to 2G

In XenServer scenarios, an additional domU is created to run OpenStack
services. This change is increasing the memory for that VM to speed up
test runs.

Change-Id: I322f4e4703e506620fa7e7456c4264ee0d050edc
Copy policy_add() from Grenade functions

policy_all() was added to Grenade's functions file, which is notmally synced
from DevStack so we need to bring it over here before the next sync.

Change-Id: Ifd852e9d1ffe39fa23f6312d1ddf2874b5f2b9f0
Merge "xenapi: Increase default OS domU memory to 2G"
Merge "remove multi-host timeout"
Merge "Copy policy_add() from Grenade functions"
Merge branch 'master' of github.com:openstack-dev/devstack