Configuration setting to generate model for all schema objects, whether used in a path or not #302

Currently when generating, the processor scans the path entries and only generates the needed models referenced by the path entries. I created a base project which defines reusable schema objects in a company standard manner. Objects such as Address, ContactInfo, etc. My subprojects import the jar as a dependency and I use maven resources to copy the yaml parts over so their definitions and references are valid. I then use the mapping file in subprojects to point to the packages/objects from the base project.

As a workaround, I created several dummy paths in the base project's openapi.yaml to get the openapi-processor to generate the models. The request is a setting so I can have no paths defined in the base project, yet still generate all model classes.