General verify options to openssl ts

General verify options to openssl ts

This commit adds the general verify options of ocsp, verify,
cms, etc. to the openssl timestamping app as suggested by
Stephen N. Henson in [openssl.org #4287]. The conflicting
"-policy" option of "openssl ts" has been renamed to
"-tspolicy". Documentation and tests have been updated.

CAVE: This will break code, which currently uses the "-policy"
option.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>