Added /liveness_check

Type of change

• Bug Fix
• Feature

#139 (closed)

Does this introduce a change in the core logic?

• [YES]

Does this introduce a change in the cloud provider implementation, if so which cloud?

• AWS
• Azure
• Google Cloud
• IBM

Does this introduce a breaking change?

• [NO]

What is the current behavior?

What is the new/expected behavior?

Added /liveness_check. Added int tests. Updated swagger doc.

Have you added/updated Unit Tests and Integration Tests?

YES