[TB] [79888872] allow SWAGGER_ prefixed env vars in JSONs
[TB] [79888872] bump ver
[TB] [79888872] allow any env var
[DC/TB] [79888872] break out interpolate_env_vars method
[TB] [79888872] make overwrite_base_path option
Merge remote-tracking branch 'origin/master' into 79888872_env_swagger
[TB] [79888872] add another test
Merge pull request #11 from primedia/79888872_env_swagger

ENV[SWAGGER_BASE_PATH]