Change MAC representation in nailgun

[Sebastian Kalinowski]

In Nailgun MAC address is a string (both in code and in DB).
Due to this 'AA:BB:CC:11:22:33' != 'aa:bb:cc:11:22:33' in many places.
This cause bugs like https://bugs.launchpad.net/fuel/+bug/1394466 which was a basically a problem with comparing lowercase MAC and uppecase MAC.

We need to:
* move MAC address in our DB to buil-in postgress type "macaddr" (http://www.postgresql.org/docs/9.3/static/datatype-net-types.html#DATATYPE-MACADDR)
* use netaddr module (https://pypi.python.org/pypi/netaddr) to compare and validate MACs.

After this it will be possible to user not only lower and uppercase MACs but also MACs in different formats.

[Ihor Kalnytskyi (ikalnytskyi)]

We can't use MAC address from built-in postgres type due to the issue:

    https://bugs.launchpad.net/fuel/+bug/1398882

[Roman Prykhodchenko (romcheg)]

Right, it's not possible to use Postgresql's embedded type for that because HW addresses for IPoIB of IPoFC or for IPoSMTH are going to have different representation.

Therefore I can see two possible solutions and both of them keep storing HW address as a string but decorated by SQLAlchemy's type decorator. The difference between them is the following:

 - The first solution assumes creation of a HWAddress type that uses netaddr.EUI underneath for manipulating standard 48 and 64 bits IEEE EUIs and custom implementations for exotic HW addresses, e.g., for IPoIB.

 - The second assumes that the type decorator represents HW addresses as netaddr.EUIs. After that it is necessary to merge support for exotic EUIs right to netaddr.

I'd say that the second approach is better. I already emailed David, the maintainer of netaddr, to ask whether he's open for this kind of changes.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/142244

[Roman Prykhodchenko (romcheg)]

ATM I have no free time to work on this. The bug requires some extra patches to be landed to upstream of netaddr and a minor update in the patch, mentioned above.

[Dmitry Pyzhov (dpyzhov)]

Waiting for upstream update

[OpenStack Infra (hudson-openstack)]

Change abandoned by Dmitry Pyzhov (<email address hidden>) on branch: master
Review: https://review.openstack.org/142244
Reason: No activity for more than a month

[Vladimir Sharshov (vsharshov)]

Moved to 8.0. It is our tech-debt.

[Ivan Ponomarev (ivanzipfer)]

let use linux standard MAC's (lowercase) format which can be found using cli tools like ip or ifconfig