TS-2191 we should not simply reschdule the http_sm if the sm_list`s mutex
is not acquired, because the client_vc`s timeout events maybe triggered.
The race may lead http_sm received a event after it is deleted.
Sub task (TS-2192)
Updated CHANGES.
TS-2217: remove the option to turn off body factory - setting it to 0
will result in empty responses

Conflicts:
	CHANGES