Support templated naming convention for containerVMs

[hickeng]

Story
As a viadmin I want to be able to enforce a naming convention for cVMs to support chargeback and other organization requirements

Detail
Container naming convention applies to the vSphere VM displayName, not to the container name itself.

[hickeng]

#6265 is a very early and not formally tested PR with basic naming convention support. The only replaceable token is {name} and that will be replace with either:
a. the name provided with docker create
b. a generated name as when --name is omitted from docker create

[hickeng]

@stuclem
A very basic form of this has been merged for engine 1.2.1 to address an urgent need. #6332 is open to polish and complete the work and has more detail than this issue, so closing in favour.
Current mechanism adds the --cnc or --container-name-convention option. This takes a name template of the form some_fixed_pattern_{replace-with-value}-static-suffix - basically just a static string conforming to existing VM naming restrictions with some replaceable tokens. Current tokens are:

• {name} - the docker pretty name for the container (either generated or supplied by docker run --name=some-name)
• {id} - the shortID of the container

This convention applies only to the vSphere display name of the VM and does not impact the names known and shown by docker.

[hickeng]

As noted but not done in previous comment, closing in favour of #6332