xenapi: Cleanup networking

OpenStack VM had 4 interfaces, from which eth0 was connected to HIMN (Host
Internal Management Network), and not used at all. The reason for not
using this interface according to johngarbutt is:
 - VNC console would not work
 - migrations would not work
 - many other things
This change removes the interface, thus devstack is providing the
same architecture as described in the official documentation, YAGNI
applied on the HIMN:

    http://goo.gl/dmrNF

The change also modifies some defaults, so it's easier to get started:
 - The Ubuntu VM is network-installed through the management network
 - OS VM is getting its address on the management network through DHCP
 - Default Public IP addresses aligned to stack.sh defaults
 - OS Services are listening on Management Interface

Related to blueprint xenapi-devstack-cleanup

Change-Id: I73c9751ade6f4786b8b682a1994cb87f0a624379
Create the /images directory used by the resize functionality.

XenServer's resize uses /images as a known-path for each hypervisor.
This is a symlink to the storage repository so disks can be moved between
the /images path and the storage repository efficiently.

Change-Id: I13b39dbf5537ad45160c1af4cc10bd867b7f89c1
Add cli_dir to tempest config

Add the cli_dir option to the generated tempest config.  This is
required on platforms such as RHEL where the binaries are not in the
standard location.

Note that to be fully operational this requires [1] in tempest so that
the cli path is created correctly.

[1] https://review.openstack.org/#/c/34302/

Change-Id: Ic7369193f1434974366cfabc7550e8545de244cd
Use lowercase section names in Neutron (aka Quantum)

Fixes bug 1194064

The DEFAULT section remains the same.

In addition to this the sql_connection has been changed to
connection - this is for OSLO DB support.

Change-Id: I56175146941a9cae966033b557e44097e29a5d43
Remove creation of Domain entries in LDAP

Domain entries are no longer stored in keystone ldap.
Removing the creation from devstack ldap install

Fixes Bug 1194204

Change-Id: I9c93d3021cc2bb058d1ef57bebcf3a13dc5bdd34
Update LVM autoextend config for RHEL6

Cinder clones are slightly larger due to some extra metadata.  RHEL6
will not allow auto-extending of LV's without this, leading to clones
giving hard-to-track disk I/O errors.

See https://bugzilla.redhat.com/show_bug.cgi?id=975052

Change-Id: I09a5e061a9665c5310383f9f9eb281bfdc8e416d
Merge "xenapi: Cleanup networking"
Merge "Create the /images directory used by the resize functionality."
Merge "Update LVM autoextend config for RHEL6"
Merge "Add cli_dir to tempest config"
Merge "Use lowercase section names in Neutron (aka Quantum)"