feat: add configName fallback resolution incl. ref path generation fix

[MKruschke]

Why the change

references paths where wrongly generated when using the --configName param (read more Issue #22)

What is the change

• the provided configName will now appended correctly to the path (fix)
• added fallback resolution to tsconfig.json if the configName couldn't be resolved

How to test

• automated test should have passed