docs(ngScenario): provide examples for element(...).query(fn)
docs(ngScenario): provide examples for element(...).query(fn)

element(selector, label).query(fn) is a very useful function, yet barely
explained. The developer guide should show how this function can be used
to conditionally execute behavior and assertions.

ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js