Fix FixtureAdapter resolve of hasMany relationship on save

When saved records through FixtureAdapter hasMany relationships were failing.
This was due to using the relationship to determine the opposite side of the
hasMany relationship instead of one of the objects.

Updated tests to prove fix.
Merge pull request #22 from KnownSubset/master

Fix FixtureAdapter resolve of hasMany relationship on save
merged fix for FixtureAdapter hasMany (from @knownsubset)
Added RequireJS structures and wrapped everything in IIFE's