don't degrade to Improvable just for session tickets (#191)
don't degrade to Improvable just for session tickets (#191)

This change causes clients without session ticket support to be allowed as
Okay. The web UI will still show the session ticket section as "Improvable" and
the JSON API will still return false for the session ticket entry.

This affects curl (the binary) and iOS clients, among others.

Fixes #169
jmhodges/howsmyssl,jmhodges/howsmyssl,jmhodges/howsmyssl