arm64 support for Darwin and Linux

[pjezek]

Is your feature request related to a problem? Please describe.
As a System Engineer I want to use cf-mngt with my M1 Mac. Be it natively as an Darwin arm64 binary or inside a Linux VM running with aarch64 architecture.

Describe the solution you'd like
I created 2 pull requests:

• cf-mgmt/pull/479
• cf-mgmt/pull/489

Describe alternatives you've considered
I am not sure if I miss a part to get those 2 new binaries each (total 4) in the automated build process.

Additional context
I am happy to test the binaries once builded.

[cf-gitbot]

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