Well first of all I'd bring `LOADING_MESSAGE` back...

# codereview

[benleggiero]

Well first of all I'd bring LOADING_MESSAGE back out of global scope, since not all classes need to see it. Maybe put it in an object RxConstants or something.

Also, why are these functions members of all `Observable`s? What's the idea behind that? Genuinely curious.

Other than that looks nice to me. Without being sure how you're using RxUtils.java or why you built it, that's the most I can say.