Implement Administration API's

[zygiert1990]

There is still some Administration API's which can be implemented, as so far we have only implemented Admin Api Keys API. Here is the list of missing API's:

• https://platform.openai.com/docs/api-reference/invite
• https://platform.openai.com/docs/api-reference/users
• https://platform.openai.com/docs/api-reference/projects
• https://platform.openai.com/docs/api-reference/project-users
• https://platform.openai.com/docs/api-reference/project-service-accounts
• https://platform.openai.com/docs/api-reference/project-api-keys
• https://platform.openai.com/docs/api-reference/project-rate-limits
• https://platform.openai.com/docs/api-reference/audit-logs
• https://platform.openai.com/docs/api-reference/usage
• https://platform.openai.com/docs/api-reference/certificates