C API examples

Please see

https://github.com/k2-fsa/sherpa-onnx/blob/master/c-api-examples/moonshine-c-api.c

and C API.

If you want to use the C++ API, which is just a wrapper around the C API, please see the following example:

https://github.com/k2-fsa/sherpa-onnx/blob/master/cxx-api-examples/moonshine-cxx-api.cc