Revamped testing guide

I understand why we may want to use globs, however I'm not sure if it needs to be mentioned here. Seeing as we are using a tests module here, I think its reasonable to assume that anything mentioned in the module guide can can apply to this module, including the use of globs. I think having this here just adds a little more to the example than perhaps is needed. Globs are also somewhat unstable from what I remember, which makes me lean more towards not recommending its use in this case.

Apologies for the nit-picking, just a thought :)