Improve savanna keystone auth configuration

We're doing to use common keystone configuration approach - section
keystone_authtoken with config opts from the python-keystoneclient
auth_token middleware.

Change-Id: Ibbe0c76ee3b00045f5cb5134bd7661e9cef6ccdd
Perform safety checks in create-stack-user.sh

This adds some safety checks to the stack user creation script.

This includes:
- Using set -o errexit to exit early on errors
- Make sure STACK_USER is set before doing anything with it

Change-Id: If027daddd03e32c5ba3c2ebb05ad5b27d2868b0a
Fix permissions for tempest.conf

The current script uses 'sudo' to copy tempest.conf.sample and thus
the .conf file gets owned by root.  It then makes the permissions 644,
meaning that when the 'stack' user does the iniset() calls, it doesn't
have permisson on the .conf file.

Since the dir has been chowned to the stack user, it seems safe to
just copy the sample file in without sudo.  In addition, I moved the
$TEMPEST_CONFIG_DIR creation closer to the copy to make it clearer
what's going on.

Seems to be related to dc4dc7f03335e26ea3d86b6184f0475cc5f3d51b

Fixes bug: #1284378
Change-Id: I103b4e90cbcfa693c9cef319f4135868a1b83de3
Merge "Perform safety checks in create-stack-user.sh"
Merge "Improve savanna keystone auth configuration"
xtrace less

we are xtrace happy, however that's just generating bulk in log
files that are mostly ignorable. For the basically bullet proof
functions we should not xtrace.

Change-Id: Iab4e6d270c1546e0db2a06395cefcdf7f7929c3c
Merge "Fix permissions for tempest.conf"
Merge "xtrace less"