Add Exchange in the test.

Increases test coverage.
zoneMatch is not used
Add line to the readme
Some docs moved to RFC status
Some documentation updates
Correct the DNSKEY flag values

See https://www.iana.org/assignments/dnskey-flags/dnskey-flags.xhtml

Elsewhere in the code 256 (1 << 8) is used numerically for ZONE, so nothing breaks for now.
Merge pull request #122 from FiloSottile/patch-1

Correct the DNSKEY flag values
Add extra (failing) sign/verify test
Cleanup the test a bit
Lowercase the Test to test
Update documentation references for EDNS0 and EDNS0_SUBNET.

Only EDNS0 is defined in RFC 6891 and EDNS0_SUBNET is actually just a draft.
Merge pull request #123 from cpatulea/master

Update documentation references for EDNS0 and EDNS0_SUBNET.
Fix ECDSA algorithms

Current code was completely wrong, so validation of ECDSA didn't work.
The new tests now works, the old one now doesn't
Fix ECDSA algorithms

Current code was completely wrong, so validation of ECDSA didn't work.
The new tests now works, the old one now doesn't
Disabled two failing ECDSA tests
Merge branch 'master' of github.com:miekg/dns
Fixed example docstring.
Added punycode conversion placeholders and...

internal functions that provide conversion and tests for those
per #120.
Moved things to subdir and adding functions to convert strings.