Add functionality for users to retrieve template by Name as well as UUID

[Belchy06]

Description

This PR adds the ability for Tink to retrieve workflows by either UUID or by Name. If the value after tink template get is not a valid UUID, Tink will default to searching for the value in the Name field of the templates.

This PR also adds a TemplateClient to the TInk client, allowing other services such as Boots to retrieve templates.

Why is this needed

This feature is required for the project I am working on but I am sure there are many other use cases I'm unaware of. Also, tinkerbell/smee#178

How Has This Been Tested?

This has been tested in the VM's based on the Local Setup with Vagrant tutorial.

How are existing users impacted? What migration steps/scripts do we need?

Checklist:

I have:

• updated the documentation and/or roadmap (if required)
• added unit or e2e tests
• provided instructions on how to upgrade

[tstromberg]

Looks good to me. Can you fix the DCO sign-off so that we could merge this?

git commit --amend --no-edit --signoff
git push --force-with-lease origin master

[rgl]

@Belchy06, was there a reason for closing this PR? Was it superseded by another one?

[mmlb]

Looks like it was mistakenly closed and then opened as a new PR in #523, which was also mistakenly close and opened as a new PR in #541.