Apply connection retry refactor, add defaults with exponential backoff

[ueshin]

Description

Applies connection retry refactor, add defaults with exponential backoff as per an item from #127.

• Refactors retry logic to use retry_connection from core.
• Adds consistent defaults with other adpaters:
  • if connect_retries and connect_timeout are not specified: 1 retry after 1s
  • if connect_retries is specified but connect_timeout is not, it will use exponential backoff

[xg1990]

Thanks a lot! Our team is eagerly waiting for this feature!

[ueshin]

Thanks! merging.