Problem: It was not possible to detect the reason for a premature
connection termination in http requests.
This patch provides a new `err` argument to the 'close' event which
can be inspected to differentiate between a timeout and a client
actively terminating the connection.
Also contains tests for this new behavior for http and https.
test/simple/test-url.js:31:(0110) Line too long (82 characters).
test/simple/test-url.js:39:(0110) Line too long (85 characters).
test/simple/test-url.js:40:(0110) Line too long (92 characters).
Taking a performance hit on 'hello world' benchmark by enabling this by
default, but I think it's worth it. Hopefully we can improve performance by
resetting the timeout less often - ideally a 'hello world' benchmark would
only touch the one timer once - if it runs in less than 2 seconds. The rest
should be just link list manipulations.
