fix(key/query sync): $key must return a model

A single instance of the sync service was being shared amongst models,
this wasn't intended.  We'll improve the interface between service and
model, but this patch makes it 'work'.

Related: #64
chore(release): bumped to v3.2.2
Merge pull request #72 from goinstant/mattcreager/hotfix-3.2.2-sync

fix(key/query sync): $key must return a model