Add spin cloud logs to view app logs on the CLI

[endocrimes]

It would be beneficial to be able to tail logs from the CLI when debugging issues, rather than needing to open the Cloud UI - especially when iterating on a deployment.

Example UX:

$ spin cloud logs my-app-name --tail
# continuously tail logs until interrupted 

$ spin cloud logs my-app-name --since=TIMESTAMP
# fetch all available logs since the given timestamp and then exit

$ spin cloud logs my-app-name --reverse
# fetch recent logs with the _newest logs first_

[seungjin]

-f instead of --tail PLEASE! :)

[seungjin]

Thanks! It works like charm!