Document "displayName" Better

[geirman]

Firstly, this looks like a great library. Well done, and the documentation looks pretty good as well. But...

The description does nothing to help someone understand how the displayName is used or why they'd care to set it. In fact, it doesn't tell me anything I couldn't already infer from the variable name itself. This is a common mistake I find in lots of documentation.

It's optional, so it would be more helpful if you told me why it exists. When would I want to bother setting this value? How is it useful? Why does this option exist? And if I set it, is it's value completely arbitrary, must it match my component's name, or what?