Add support for svc get <name> (match by name instead of id)

[murrayju]

This implements tiger svc get <name>, such that we'll return a match by the service's name (in addition to id).

If exactly one service matches, the full details are displayed and the exit code is 0 (success)

If multiple services have the same name, the process exits with code 8 (so scripts can handle this explicitly), while printing an error message and the list of ambiguous services.

Exit code 6 is used when there are no matches

All other flags works as normal.