Update langtour > interfaces

[butlermatt]

Reflect removal of interface keyword, and removal of 'default' classes for interfaces.

[sethladd]

Our general style is to use can.

[sethladd]

Thanks Matt! The timing of this is challenging, we're going to publish a significant rewrite of this guide, which will make your changes redundant. We really like your contributions. Let's meet over a Hangout to coordinate, there's lots of other places where you can help. :)

[butlermatt]

Thanks Seth. I wasn't sure of this change myself to be honest due to the extent of the changes rather than just a coupe of typo fixes. But thought I'd give it a hook anyways. Truthfully as you said this section deserves a full rewrite rather than just an adaptation I attempted.

I'd be happy to me up on hangout sometime to discuss other ways I may be able to help out.

[butlermatt]

Since the re-write for this guide is already in the pipe-line would you like to (or like me to) close this pull request? Alternatively I can make some of the changes you suggested (for which I appreciate as well, as it provides insight for future patches as well).

Thanks,
Matt

[sethladd]

I hate to say it, but let's close this request. We'll sync to get you involved in other areas of the site. Thanks again for the patch!

[butlermatt]

I'm perfectly ok with closing it. Makes it easier for me to send a new pull request for something different (and smaller ;)
As I mentioned I was aware of the work that really should have had anyways, but thanks again for the comments on it. They help significantly.
Matt