Fix failing tests, upgrade to should 4.0

[mjackson]

When I tried to clone the repo and run the tests, 9 of them were failing. Needless to say, it's a little unsettling to use a testing framework with failing tests.

I fixed the failing tests and upgraded the should dev dependency to 4.0. Seems the tests were failing because they were looking for properties on should's Assertion object that were not present, namely status and include.

[jonathanong]

wwtttfff

[travisjeffery]

they pass for me locally, and on travis-ci: https://travis-ci.org/visionmedia/mocha/builds/26212339

here's what i get when i merge your branch and npm install, seems busted with older versions of npm/node:

npm WARN package.json growl@1.7.0 No repository field.
npm http GET https://registry.npmjs.org/should
npm http 200 https://registry.npmjs.org/should
npm ERR! Error: No compatible version found: should@'^4.0.0'
npm ERR! Valid install targets:
npm ERR! ["0.0.1","0.0.2","0.0.3","0.0.4","0.1.0","0.2.0","0.2.1","0.3.0","0.3.1","0.3.2","0.4.0","0.4.1","0.4.2","0.5.0","0.5.1","0.6.0","0.6.1","0.6.2","0.6.3","1.0.0","1.1.0","1.1.1","1.2.0","1.2.1","1.2.2","1.3.0","2.0.0","2.0.1","2.0.2","2.1.0","2.1.1","3.0.0","3.0.1","3.1.0","3.1.1","3.1.2","3.1.3","3.1.4","3.2.0-beta1","3.2.0","3.3.0","3.3.1","3.3.2","4.0.0"]
npm ERR!     at installTargetsError (/usr/local/lib/node_modules/npm/lib/cache.js:719:10)
npm ERR!     at /usr/local/lib/node_modules/npm/lib/cache.js:641:10
npm ERR!     at saved (/usr/local/lib/node_modules/npm/node_modules/npm-registry-client/lib/get.js:138:7)
npm ERR!     at Object.oncomplete (fs.js:297:15)
npm ERR! If you need help, you may report this log at:
npm ERR!     <http://github.com/isaacs/npm/issues>
npm ERR! or email it to:
npm ERR!     <npm-@googlegroups.com>

npm ERR! System Darwin 13.2.0
npm ERR! command "/usr/local/bin/node" "/usr/local/bin/npm" "install"
npm ERR! cwd /Users/tj/dev/mocha
npm ERR! node -v v0.8.26
npm ERR! npm -v 1.2.30
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /Users/tj/dev/mocha/npm-debug.log
npm ERR! not ok code 0

same thing happens on travis-ci too: https://travis-ci.org/visionmedia/mocha/jobs/26315283

[mjackson]

@travisjeffery You need to use npm 1.3.x (I believe) to use dependencies specified using the ^4.0.0 format. I can try specifying the dependency as ~4.0.0 if you prefer.

[travisjeffery]

better to be more specific anyway since what was wrong there was a bad should dependency

thanks for the pr

[dougwilson]

You need to use npm 1.3.x (I believe) to use dependencies specified using the ^4.0.0 format.

Specifically, >= 1.3.13