Adds a note and link to installing PhantomJS to run smart-answer tests locally.
Adds a note and link to installing PhantomJS to run smart-answer tests
locally.

stwalsh/smart-answers,stwalsh/smart-answers,aledelcueto/smart-answers,alphagov/smart-answers,stwalsh/smart-answers,aledelcueto/smart-answers,alphagov/smart-answers,alphagov/smart-answers,stwalsh/smart-answers,aledelcueto/smart-answers,alphagov/smart-answers,aledelcueto/smart-answers