Test persistent HTTP connections using mock socket object
Test HTTP connection dropping using HTTPServer in another thread
Test for broken pipe trigger
Test for non-idempotent HTTP method retrying
Handle broken pipe and reset errors; only retry for idempotent methods
Note about not reusing connection with “virtual hosts”
Merge upstream

Conflicts:
	test.py
Drop dependence on undocumented BadStatusLine implementation
Drop stderr auto buffering; unittest --buffer can be used instead
Merge remote-tracking branch 'patig/http'

Conflicts:
	test.py