Added a function `enable_rhrepo_and_fetch_repoid` and few fixes.

Added `enable_rhrepo_and_fetch_repoid` function, to group many
steps required for syncing RedHat Repos.

The `sync` function under `Repository` Class now returns a task_id.

Added and Fixed many docstrings.

Updated the import related to cloning manifests.

Added test related to syncing RedHat Repository

Few fixes after Repository.sync returns task_id

Fix the check for response.raise_for_status

Moved the sync test case to test_repository_v2

Fetching the product_id now uses products api path

Moved the function  enable_rhrepo_and_fetchid to the test module
Merge pull request #1442 from kbidarkar/add-sync-api-tests

Added a function `enable_rhrepo_and_fetch_repoid` and few fixes.