Parent Issue: https://github.com/elastic/response-ops-team/issues/208

Implement the ability to create and update rules with rule specific flapping setting. This includes all of the schema and validation changes required to make this happen.

Requirements:

• User can create a rule with flapping
• User can update a rule with flapping
• User should not be able to create a rule with flapping if global flapping is disabled
• User should not be able to update a rule with flapping if global flapping is disabled
• Flapping should be validated