No Error on deleting non-existing Document

[Mopsgeschwindigkeit]

With executing fuego delete col/<non-existing-id> you do not get an error message. This could lead to some probems in case of a typo.

Adding an additional flag to enable an 'existence check', could solve the issue. e.g.

$ fuego delete --check-existence col/<non-existing-id>
Error: Trying to delete non-existing document