Chaining backend.use calls

[droganov]

To allow:
backend
.use( "submit", function( shareRequest, next ){
console.log( "submit" )
next()
}
)
.use( "query", function( shareRequest, next ){
console.log( "query" )
next()
}
)

[nateps]

Reasonable given that people may be used to this from Express.

Can you please add a unit test? PRs for any new feature or bug fixes should include a unit test.

[droganov]

Please give me a time to pick it up, I'm new to this travis stuff

[droganov]

@nateps am I adding use test to sharedb/test/db.js?

[nateps]

the test files basically correspond to each feature. appropriate test should be added to: https://github.com/share/sharedb/blob/master/test/middleware.js

You don't need to mess around with Travis; simply run the unit tests locally with npm test, which will use mocha locally.