bug(deploy): issue checking for firebase-tools version when not installed

[prescottprue]

Do you want to request a feature or report a bug?
Bug

What is the current behavior?

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via https://jsfiddle.net or similar.

What is the expected behavior?
It should still exit with 1, but the error message should be more clear (i.e. "firebase-tools version not found")

Which versions of dependencies, and which browser and OS are affected by this issue? Did this work in previous versions or setups?