[Bugfix] Decouple DS.EmbeddedRecordsMixin from DS.ActiveModelSerializer

[Fixes #1974]
better error for missing inverse on hasMany/belongsTo
Merge pull request #2009 from knownasilya/inverse-msg

better error for missing inverse on hasMany/belongsTo
Revert "better error for missing inverse on hasMany/belongsTo"

The commit was using Ember.isBlank which is still feature flagged.

This reverts commit f2ffe0715e6a778db05c65a501248a2d500100e5.
adapt usage example for TemperatureTransform

Adapt usage example to reflect the TemperatureTransform. 'raw' doesn't make sense here as it is not registered as such.
Merge pull request #2014 from jwahdatehagh/patch-1

adapt usage example for TemperatureTransform
Better error for missing inverse on hasMany/belongsTo
Merge pull request #2016 from emberjs/pr2012Cleanup

Better error for missing inverse on hasMany/belongsTo
Fix class name in debugging message

`RestAdapter` should be `RESTAdapter`.
Merge pull request #2019 from tricknotes/fix-class-name

Fix class name in debugging message
Fixed a loose semicolon

Semicolon was unnecessary and causing a javascript error.
Merge pull request #2022 from rmartinez93/master

Fixed a loose semicolon
updated '_links' to just 'links'
Merge pull request #2024 from dadamssg/master

updated '_links' to just 'links'
fix documentation of `getById`
Merge pull request #2025 from Crunch09/master

fix documentation of `getById`
Merge pull request #1987 from pixelhandler/keyForAttribute-optional

[Bugfix] Decouple EmbeddedRecordsMixin from ActiveModelSerializer
fix documentation of 'attr'
Merge pull request #2027 from JustAboutJeff/DOCS-fix-attr

fix documentation of 'attr'
Added documentation for ajaxError with DS.Errors.