added globbing feature

it is now possible to use wildcards in the certificate configuration
of a token. the wildcard (and any other portion of the string) may
be enclosed in round brackets, e. g. foo(*).bar
in the key definition captured matches can then be used as $1, $2 etc, e. g.
certificate: $(crypto.base_dir)/kn(*)-cert.pem
key: $(crypto.base_dir)/kn$1-key.pem