Return created/updated objects

[shota]

WHY are these changes introduced?

Currently, we can't fetch responses from REST API. This has a lot of problems when a user wants to do something with the created object.

WHAT is this pull request doing?

• Return response data array
• Store updated object when save(true) or saveAndUpdate()

Type of change

• Patch: Bug (non-breaking change which fixes an issue)
• Minor: New feature (non-breaking change which adds functionality)
• Major: Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• I have added a changelog entry, prefixed by the type of change noted above
• I have added/updated tests for this change
• I have updated the documentation for public APIs from the library (if applicable)

[shota]

I have signed CLA with my company