Enhancement: Improve error logging in ocmd flow

https://github.com/cs3org/reva/pull/3530
https://github.com/cs3org/reva/pull/3526
https://github.com/cs3org/reva/pull/3419
https://github.com/cs3org/reva/issues/3365
https://github.com/cs3org/reva/pull/3369
