Add a functional test example

[skliper]

Is your feature request related to a problem? Please describe.
APIs should have functional tests that verify implementation within operational context (full stack, not stubs). Coverage tests can not fully exercise intended functionality since they utilize stubs.

Describe the solution you'd like
Add example use of the cFE Functional test framework

Describe alternatives you've considered
None

Additional context
None

Requester Info
Jacob Hageman - NASA/GSFC