Added emphasis to the Hint

Maybe because late/tired but I read the Hint exactly backwards — as such I made an error I may not have (and spent some time working it out). 

The added emphasis should save someone else the issue.
use correct bound propety

code and the example below should be similar
Incorrect JSON format shown for belongsTo relationship

The documentation for the chapter "Connecting to an HTTP Server" shows an incorrect JSON format for the belongsTo relationship.  Currently has the relationship in an "_links" property, but Ember Data is actually expecting the id for the user against the "user" property.
Merge pull request #908 from lindyhopchris/patch-1

Incorrect JSON format shown for belongsTo relationship
Add note to component definition guide
Merge pull request #911 from alexspeller/improve-component-docs

Add node to component definition guide
Remove debugging tips for using a record's stateManager
Adds Ember.js Puerto Rico Meetup
Merge pull request #913 from gcollazo/master

Adds Ember.js Puerto Rico Meetup
Merge pull request #912 from benmoss/removeStateManagerTips

Remove debugging tips for using a record's stateManager
Update adding_css_classes_to_your_components_based_on_properties.md

Removes partial sentence.
Merge pull request #914 from jehoshua02/patch-1

Update adding_css_classes_to_your_components_based_on_properties.md
Update displaying_formatted_dates_with_moment_js.md

For some reason the markdown renderer isn't picking up the unordered list. Maybe a newline will help?
Merge pull request #915 from jehoshua02/patch-2

Update displaying_formatted_dates_with_moment_js.md
Merge pull request #907 from ryrych/patch-3

use correct bound propety
Merge pull request #905 from carltongibson/patch-1

Added emphasis to the Hint
Merge branch 'master' of https://github.com/emberjs/website