Preserve errors received from service on revalidation.

Errors received from remote service will be stored in a separate
error hash and will be add them to default error hash on revalidation
due to `valid?` call. This will resolve problems with resources being
valid because `valid?` reset remote errors.

Currently it is required to manually clear `remote_errors` before
retrying to save a fixed resource.
Fix parameter ordering bug on stubs.

This will fix a stub bug where `raise` parameter is ignored if a
`return` parameter is defined before.
Bugfix release 0.22.2