update middleware page

[Matt Krick]

• top of middleware page says scServer, examples say wsServer. Should all say scServer.
• Nothing mentions the interface for req (data, waitForAuth, socket...)

will PR when i finish the sprint & find more stuff as I read the guide with fresh, forgetful eyes 😄

[Jonathan Gros-Dubois]

@mattkrick If you look under subscribe method http://socketcluster.io/#!/docs/api-scsocket-client - It has info about waitForAuth, but yeah it doesn't currently show the data option.

Feel free to make a PR if you get the time.

[Jonathan Gros-Dubois]

@mattkrick Thanks, should be fixed now... Finally ;p
https://socketcluster.io/#!/docs/middleware-and-authorization