Mention segwit activation in release notes.
Mention segwit activation in release notes.

Add the planned Segwit activation to the Namecoin 0.18 release notes
(https://github.com/namecoin/namecoin-core/pull/302).

namecoin/namecoin-core,pataquets/namecoin-core,pataquets/namecoin-core,namecoin/namecore,namecoin/namecoin-core,namecoin/namecoin-core,namecoin/namecore,domob1812/namecore,pataquets/namecoin-core,pataquets/namecoin-core,namecoin/namecoin-core,namecoin/namecoin-core,domob1812/namecore,namecoin/namecore,domob1812/namecore,domob1812/namecore,domob1812/namecore,namecoin/namecore,namecoin/namecore,pataquets/namecoin-core,pataquets/namecoin-core,namecoin/namecore,namecoin/namecoin-core,domob1812/namecore