Implement CI in transpiler

[tbm0115]

Once CI is configured on the SysML model (see mtconnect_sysml_model repo), then the XmiTranspiler should have an option to pull down the latest release of the model.

This should be accomplished using GitHub's download API:

https://github.com/{owner}/{repository}/releases/download/{version}/name_of_asset

Example:
https://github.com/mtconnect/mtconnect_sysml_model/releases/download/v1.5/Model.xml

This will also require that the XMI document for the SysML model be included in the release package in a consistent manner for each release.