Multiple YAML Configuration Support

[AarC10]

Is your feature request related to a problem? Please describe.
In the near future, we may have multiple YAMLs for defining types and measurements since we want to support autogenerated code for FSW too.

Describe the solution you'd like
Have the GSW service parse a group of YAMLs within a folder instead of a specific YAML itself. Have the parser also look for an include label which can label other directories that may contain YAMLs.

Additional context
Care should be taken in avoiding circular includes with YAMLs. This can be done by storing absolute file paths as a set and preventing parsing from occurring if in the set. We should at least get basic support in first though and this can be made a separate issue if the PR is too big