Include test to show error introduced with last embedded changes
AdapterPopulatedRecordArray triggers `didLoad` event at the end of the runLoooop

- Fixed reported integration tests
- Add Em.run to some tests which became invalid with this change
This allow to define integer ids in the fixtures, as well as integers

correct test title
Make DS.RESTAdapter default adapter of DS.Store
Add a space in the assertion message
Merge pull request #615 from Myslik/master

Make DS.RESTAdapter default adapter of DS.Store
Merge pull request #618 from marktheunissen/minor-type-in-assertion

Add a space in the assertion message
Merge pull request #605 from sly7-7/fixture-adapter-coerce-ids

Allow to define integer ids in the fixtures, as well as string
Merge pull request #580 from ppcano/load-async-error

Trigger didLoad event in the `AdapterPopulatedRecordArray` at the end of the runloop
Demonstrate unwanted record sharing.

By adding a pingbacks relationship and not modifying it in any test, we
should end up with an empty array in all serialized Posts, i.e.

    {
        "post": {
            "comments": [
                {
                    "title": "Wouldn't a more lightweight...",
                    "user": null
                },
                {
                    "title": "This does not seem to reflect...",
                    "user": null
                }
            ],
            "pingbacks": [],
            "title": "A New MVC Framework in Under 100 Lines of Code"
        }
    }

However, what we get is

    {
        "post": {
            "comments": [
                {
                    "title": "Wouldn't a more lightweight...",
                    "user": null
                },
                {
                    "title": "This does not seem to reflect...",
                    "user": null
                }
            ],
            "pingbacks": [
                {
                    "title": "Wouldn't a more lightweight...",
                    "user": null
                },
                {
                    "title": "This does not seem to reflect...",
                    "user": null
                }
            ],
            "title": "A New MVC Framework in Under 100 Lines of Code"
        }
    }
Consider relationship for embedded hasMany records.

When serializing a relationship, the previous algorithm serialized all
records in _all_ has-many relationships, not just all records for the
specified relationship.
Only serialize has-manys that are embedded
Using FixtureAdapter, ids must be defined in the FIXTURES
improve error message
Merge pull request #624 from sly7-7/fixtures-must-have-ids

Fixtures must have ids