add tests

package.json

 {
   "name": "clearbit",
-  "version": "1.2.1",
+  "version": "1.2.3",
   "description": "Client for Clearbit.co business intelligence APIs",
   "main": "./src",
   "scripts": {

src/risk.js

@@ -3,7 +3,7 @@
 var resource = require('./resource');
 
 exports.Risk = resource.create('Risk', {
-  api: 'Risk'
+  api: 'risk'
 })
 .extend(null, {
   calculate: function(options) {

test/fixtures/risk.json

+{
+  "email": {
+    "valid": true,
+    "socialMatch": true,
+    "companyMatch": true,
+    "nameMatch": null,
+    "disposable": false,
+    "freeProvider": false,
+    "confirmed": false,
+    "blacklisted": false
+  },
+  "address": {
+    "geoMatch": null
+  },
+  "ip": {
+    "proxy": false,
+    "geoMatch": null,
+    "blacklisted": false
+  },
+  "risk": {
+    "level": "low",
+    "score": 0
+  }
+}

test/risk.js

+'use strict';
+
+var expect = require('chai').expect;
+var nock   = require('nock');
+var Risk   = require('../')('k').Risk;
+
+describe('Risk', function () {
+
+  var mock;
+  before(function () {
+    mock = nock('https://risk.clearbit.com');
+  });
+  after(nock.cleanAll);
+  afterEach(function () {
+    mock.done();
+  });
+
+  describe('Risk#search', function () {
+
+    var fixture = require('./fixtures/risk');
+
+    it('can calculate risk', function () {
+      mock
+        .get('/v1/calculate?email=alex%40clearbit.com&ip=127.0.0.1')
+        .reply(200, fixture);
+
+      return Risk.calculate({email: 'alex@clearbit.com', ip: '127.0.0.1'})
+        .then(function (response) {
+          expect(response)
+            .to.be.an.instanceOf(Risk)
+            .and.have.deep.property('risk.score', fixture.risk.score);
+        });
+    });
+
+  });
+
+});