Bug 1074468 — Add calleeId logs on POST /calls/:token
Rename userMac to userIdHmac.
revert renaming
make sure we check for userMac
use userMac "h4x0r" in both spots
check that we log callerId and calleeId
Merge pull request #225 from mozilla-services/1074468-log-callerId-calleeId

Bug 1074468 — Add calleeId logs on POST /calls/:token