Fix previous change to not madly leak memory.

activity.

Consequent Constification

with allocating its own objcores.

When WRW is used to send stuff to the backend 'req->t_resp' is not
an appropriate base for the timeouts.

We now have:
	VSL() -> send directly to global VSL buffer
	VSLb() -> send to buffered VSL
	VSLbt() -> send txt to buffered VSL

Fixes #1056

the "real streaming" code we are working on.

Fixes: #1092