Extend OAI specification (swagger) definition with pagination parameters

Problem Definition

The OAI specification schema for Bitbucket Cloud API (https://api.bitbucket.org/swagger.json) includes the definition of the fields `page` and `pagelen` for a few endpoints, like the pull request commits and some of the code search endpoints. The rest of the paginated objects do not include a definition of these fields.

Suggested Solution

The request is to add definitions for `page` and `pagelen` in the swagger for all paginated objects, so clients can properly get generated with pagination support.