Scope method should return cached relation value (sync)
hasMany through - sync scope getter
hasOne - test sync scope getter
polymorphic hasMany - test sync scope getter
hasAndBelongsToMany - test sync scope getter
embedsMany - implement sync scope getter
Test .value() method - as used by scope getter
Enforce id (prevent user-set value), fix isNewRecord
More fixes/tests
DAO save() now uses isNewRecord()
Tiny fixes
Merge pull request #288 from fabien/fix/relation-tests

Test sync (cached) relation getters
Merge pull request #290 from fabien/feature/enforce-id

Enforce id (prevent user-set value), fix isNewRecord
Merge pull request #295 from fabien/fix/embeds-many

Various improvements to embedded relations
Fix to handle new isNewRecord implementation