Improve IO::Socket::INET.accept() documentation.
Improve IO::Socket::INET.accept() documentation.

Specify that a new socket instance is returned by such method.
Close issue #1929.

Description as of rakudo source 2018.01.

jonathanstowe/doc,stmuk/doc,MasterDuke17/doc,perl6/doc,stmuk/doc,jonathanstowe/doc,MasterDuke17/doc,dmaestro/doc,dmaestro/doc,dmaestro/doc,stmuk/doc,tbrowder/doc,perl6/doc,jonathanstowe/doc,perl6/doc,dmaestro/doc,jonathanstowe/doc,jonathanstowe/doc,perl6/doc,tbrowder/doc,stmuk/doc,stmuk/doc,perl6/doc,dmaestro/doc,MasterDuke17/doc,MasterDuke17/doc,tbrowder/doc,tbrowder/doc