Add angular highlighting for $element and $attributes

[tandrewnichols]

The list of built-in services in #1 is fairly complete, but in directives, there are also $element and $attributes that can be injected. $element is just a jQuery object, so it wouldn't have any methods attached to it that would need to be highlighted (if jQuery highlighting is already turned on). $attributes has a few methods, however. From the docs here: $normalize, $addClass, $removeClass, $updateClass, $observe, $set, and $attr. (That last is actually just a property and not a function.) Any chance similar highlighting could be added to these things as is on the built-in services (e.g. $scope.$eval)?

[tandrewnichols]

Example (non-)highlighting:

$scope is highlighted, but $attributes and $observe are not.

[tandrewnichols]

Awesome, thanks!