Attribute labels are mainly used for display purpose. For example, given an attribute
firstName, we can declare a label
First Name which is more user-friendly and can
be displayed to end users.
By default an attribute label is generated using
Model::generateAttributeLabel.
This method allows you to explicitly specify attribute labels.
Note, in order to inherit labels defined in the parent class, a child class needs to
merge the parent labels with child labels using functions such as
array_merge().