Standardize arch support for CLI project in general

[iancoffey]

Describe the feature request
We should standardize what os architectures are supported for the CLI and larger project.

Collated Context

Context from 2021-02-05 17:24:12
User: mattmoyer
Another issue that might come into play here is dependence on native system libraries. This might happen, for example, if we integrate the session storage in the tanzu login command with system keychain on macOS. As far as I know, all the good ways to do this use CGO and prevent cross-compilation.

It shouldn't be a huge problem, but it might mean that if we want to ship macOS ARM binaries, we need an ARM macOS build machine.

Context from 2021-02-05 17:31:44
User: zjs

As far as I know, all the good ways to do this use CGO and prevent cross-compilation.

For tag builds, we can leverage the VMware build infrastructure. That should provide good coverage of architectures/platforms for natively compiled builds.

Context from 2021-02-26 13:14:42
User: iancoffey
I will start with proposing we implement this matrix, and gain feedback:

OS	Arches
Darwin	amd64 Arm64
FreeBSD	amd64
Linux	amd64 arm64
Win	amd64