Update README.md

README.md

 # packetdrill
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 A fork of [packetdrill](https://code.google.com/p/packetdrill/) which adds support for
 * UDPLite as specified in [RFC 3828](https://tools.ietf.org/html/rfc3828)
 * SCTP as specified in [RFC 4960](https://tools.ietf.org/html/rfc4960),  [RFC 4820](https://tools.ietf.org/html/rfc4820) and [RFC 7053](https://tools.ietf.org/html/rfc7053)