Write errors to stderr instead of stdout

[matbech]

On Windows x64, errors are written to stdout instead of stderr. For example, in the following example:

Engine "pkcs11" set.
Hash method is SHA256
Warning: Ignore -h option, use the hash algorithm specified in AppxBlockMap.xml
Signing as a package
Connecting to http://timestamp.digicertddvd.com
CURL failure: Couldn't resolve host name http://timestamp.digicertddvd.com
RFC 3161 timestamping failed
Use the "-t" option to add the Authenticode Time-Stamp Authority or choose another one RFC3161 Time-Stamp Authority
Unable to set unauthenticated attributes
E8B00000:error:0300007F:digital envelope routines:evp_pkey_get0_RSA_int:expecting an rsa key:crypto\evp\p_legacy.c:37:
Failed

The part starting from "CURL failure .." should be written to stderr.

Platform: Windows 11 x64