Add --debug flag to show info about request and response

This MR adds a new --debug (global) flag. When used, the output will show more information about:

• sent request details
• assets as a JSON object, after receiving a response.

Manual testing

create call without the --debug flag:

create call with the --debug flag:

get call without the --debug flag:

get call with the --debug flag:

get call with the --debug flag on non-existent release:

Closes #70 (closed)