Adding user-agent as some services require
(cherry picked from commit 8ca8764bb356d67306eeba0f7db642f81c5ca723)
Fix PR14247

Add "Connection: close" to requests that we know will end after one
request.

Read upto 1K bytes at a time on requests rather than just 1 at a time.

Note: edited to remove abandon -> close changes
(cherry picked from commit 87135b110bdf147655e9bd73d68880905834c6d4)
updated stepper HISTORY.

Please merge to 6.0 release
(cherry picked from commit e3efaf5f05e94d36d4450400641ac4ec2560b0aa)
oops 6.0 not 5.6, silly rabbit.

Please merge to 6.0 release
(cherry picked from commit ed0a5ae45e6dcad054c441a1638c418e4539a46c)
Fix test cases for close?
(cherry picked from commit 4dd594a291f26310916dedfec678b1c7393f9ef5)