Upgrade to httplike 1.0.1.

This simply upgrades to the new httplike, and adjusts for the minor API changes.

The bad CSeq test suddenly surfaced after this. I applied the second commit to fix it.

When applying that commit on the old code that still uses httplike 0.0.8, the test stalls. So I guess this has to do with the pipelining issue that was fixed in httplike.
Hm, was this test just broken before? (i.e. only checking the very first CSeq?)