allow for handler setting of the "connection" header

The websocket protocol requires the returning of "upgrade" in the
:CONNECTION return header. This commit makes START-OUTPUT not clobber
a set :CONNECTION.
Merge pull request #69 from whalliburton/master

allow for handler setting of the "connection" header
release 1.2.25
Close SSL streams after processing connection.

Otherwise it leaks foreign memory.

Reported by José Ronquillo.
Optimize get-peer/local-address-and-port.

Instead of calling USOCKET:GET-X-ADDRESS and USOCKET:GET-X-PORT
separately, call GET-X-NAME, which returns address and port as two
values. At least for SBCL GET-X-ADDRESS and GET-X-PORT are implemented
as NTH-VALUE 0/1 of GET-X-NAME, which causes the address to be consed
twice.