implement supplementary claims
use "udc" attribute for user disclosed claims
Checkpointed:

update Windows code for userAssertedClaims
update for userAssertedClaims

Conflicts:
	libbrowserid/bid_wk.m
add BID_S_MISSING_CERT_BINDING/BID_S_CERT_BINDING_MISMATCH
s/udc/attr-certs
use separate metadata claim