test(pageObjects): Added rxEnvironment Page Object

Added a page object for rxEnvironment. getEnv returns the current environment.
We won't block this PR on this, but in general I'm not a fan of passing boolean parameters to functions. Too often you then see things like `isProd(true)` and it's hard to tell what that actually means. I prefer using `isProd()` and `isProdOnBaseUrl()`. See http://silkandspinach.net/2004/07/15/avoid-boolean-parameters/ for a super concise example