Improve the networks validation for nova server

[huangtianhua]

Nova doesn't allow specify 'port_id' if using nova-network:
https://github.com/openstack/nova/blob/master/nova/api/openstack/compute/servers.py#L460-L465

Improve the validation of nova server according the above constraint.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/273324

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/273324
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=967df0e92dc6cf3f733a204f097a8e3283881c82
Submitter: Jenkins
Branch: master

commit 967df0e92dc6cf3f733a204f097a8e3283881c82
Author: huangtianhua <email address hidden>
Date: Thu Jan 28 11:08:39 2016 +0800

    Adds validation to support 'port' only if using neutron

    If not using neutron, nova doesn't allow to specify
    'port' parameter when create server. This patch adds
    validation to support 'port' only when using neutron.

    Also, this patch fixes another problem:
    the commit 84564a3665b07c13b4e3909a7d7949388c1f5c6c
    has been merged, there is a problem in the case: user
    specify 'network', 'fixed_ip' and 'port' in nova-network,
    the ip will be ignored, and then nova will raise exception:
    https://github.com/openstack/nova/blob/master/nova/api/openstack/compute/servers.py#L460-L465.

    Change-Id: I1c1cc236e2f2b6d50cc15034e5854de429bf8be0
    Closes-Bug: #1538407
    Partial-Bug: #1533074

[Thierry Carrez (ttx)]

This issue was fixed in the openstack/heat 6.0.0.0b3 development milestone.