sws.c: HTTP and GOPHER test server-side connection closing adjustment

When, for a given test, server is instructed to close connection after
server reply we now wait a very small amount of time (50ms) before doing
so. This is done to allow client to, at least partially, read server
reply before getting an ECONNRESET.

The above is required to make test cases 1070, 1200, 1201 and 1202 pass
with Cygwin 1.5.X on W2K.

GOPHER test server closes connection after _every_ server-reply, as such,
at some point it could require a bigger time or using shutdown() before
a server-side initiated disconnection.