This is a WIP, but currently covers all basic Contacts API methods and Oauth2 authentication process:
Get authorization URL.
Request Access Token.
Automatically refresh token if it has expired.
Listing Contacts using the /ids endpoint, only returning the ids (faster).
Utility shortcut methods to find by the main available search fields, both by exact match ("is" operator) and partial match ("contain" operator).
Search Contacts by id