Connection close header error

[DobromirM]

When a Connection: close header is sent with a request, the HTTP server closes the connection BEFORE sending the response and then it fails when trying to respond to the closed connection.

According to RFC 2616 the connection should be closed after the response is sent:

HTTP/1.1 defines the "close" connection option for the sender to
signal that the connection will be closed after completion of the
response. For example,

   Connection: close

in either the request or the response header fields indicates that
the connection SHOULD NOT be considered `persistent' (section 8.1)
after the current request/response is complete.

[DobromirM]

This is the code that causes the issue:

swim/swim-java/swim-runtime/swim-core/swim.io.http/src/main/java/swim/io/http/AbstractHttpServer.java

Line 66 in 415974b

this.close();