Add no-store, no-cache in Cache-Control headers

[Bharat23]

Changes

• Removed the logic to never use cache if either of no-cache/no-store was present
• Instead they work as follows
• no-cache: doesn't use cache even if the value is present but stores the response in the cache
• no-store: can use cache if present but will not add/update to cache
• If both are passed, it will neither store nor use the cache. Will remove the max-age and ETag as well.
• Test cases

Associated Issue: #144