feature: operationId generator v2 compatibility mode

[shockey]

Description

This PR adds a top-level v2OperationIdCompatibilityMode option to Swagger-Client.

Motivation and Context

Fixes #1269!

How Has This Been Tested?

I added a handful of unit tests that should cover the ID generator code, and the top-level option efficacy.

Types of changes

• No code changes (changes to documentation, CI, metadata, etc)
• Dependency changes (any modification to dependencies in package.json)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.