- Previously, `expect(obj).not.property(name, val)` would throw an Error
if `obj` didn't have a property named `name`. This change causes the
assertion to pass instead.
- assert.propertyNotVal renamed to assert.notPropertyVal
- assert.deepPropertyNotVal renamed to assert.notDeepPropertyVal

- Previously, the `deep` flag had unexpected behavior when used with the
`property` assertion: Instead of switching from strict to deep equality,
it unlocked the ability to use dot and bracket notation when referencing
property names. This behavior now belongs to the new `nested` flag.
- assert.deepProperty renamed to assert.nestedProperty
- assert.notDeepProperty renamed to assert.notNestedProperty
- assert.deepPropertyVal renamed to assert.nestedPropertyVal
- assert.notDeepPropertyVal renamed to assert.notNestedPropertyVal