Stop using squirrelly functions from assert:

"Knowing what we now know, if we were designing/building Node.js core all over again, the assert module would either not exist in Node.js or else consist of far fewer functions--quite possibly just assert() (which is currently an alias for assert.ok())."

see nodejs/node#5312 (comment)

src/test/index.js

@@ -3,12 +3,13 @@ var affaGuid = require('..')
 
 describe('affa guid', function () {
   var N = 1000
-  var generated
 
   before(function () {
     assert(N >= 2, 'Tests need multiple UUIDs to be generated')
   })
 
+  var generated
+
   beforeEach(function () {
     generated = {}
     for (var i = 0; i < N; i++) {
@@ -23,6 +24,6 @@ describe('affa guid', function () {
   })
 
   it('Generates UUIDs that are unique each time', function () {
-    assert.strictEqual(Object.keys(generated).length, N)
+    assert(Object.keys(generated).length === N)
   })
 })