ndb: start implementing existing NostrEvent functionality (William Casarin)

ndb/test: add a few more tests (William Casarin)

ndb: add subscript and count for TagsSequence (William Casarin)

mentions: add ndb mention parser (William Casarin)

iter: make safer by using NdbNote instead of unsafe pointers (William Casarin)

misc: don't immediately hex encode event commitment (William Casarin)

ndb: add content and owned_size (William Casarin)

ndb: add pubkey to NdbNote (William Casarin)

ndb: update lib (William Casarin)

move copyndb to the right folder (William Casarin)

test: fix build and tests (William Casarin)

pushed to refs/heads/master

http://git.jb55.com/damus/commit/7ec8da6c73b8ed7203678bb7770a52126d85a0f7.html