Replace test library

[sandfox]

The current test library has been depreciated for around 3 years but somehow still works. We should probably replace it with something maintained like tap or lab etc before it gets broken by a new release of node.

Open to suggestions or PRs for this. It's going to be a fair chunk of work to rewrite everything I suspect.

[felixfbecker]

@sandfox I'm trying to take a shot at it because my other PR is finished but I cannot run the expresso tests on Windows. However I don't understand the tests at all, some inline documents would have been helpful. There is no such thing as beforeExit and mocha, instead you call done with either an error or without one for async tests. The way you iterate synchronously with a for loop and then trigger async actions and the assert synchronously doesn't make sense to me...

Maybe you have some input, otherwise I will just take the existing test descriptions and write new ones for them, make them pass on the current version and then test against my prototype-PR.

[felixfbecker]

But I'm not even sure what expands to max limit even means - what is it in this context?

[felixfbecker]

Btw mocha needs at least Node 0.8, which means we cannot test on Travis for Node 0.2 anymore.

[sandfox]

Ok, I'll have a look and see if I shed any further light on that stuff and drop it here

I'm totally fine with dropping testing for everything pre-0.8 - as long as the new tests pass I'm happy with line of reasoning that we haven't broken backwards compatibility for library consumers (which ever ones are still out there on old skool node versions), and when the "class" stuff lands, as long as the tests still pass then in theory we still won't have broken b/c.

[sandfox]

done in v3