Update grunt-contrib-jshint and add globals config

.jshintrc

@@ -16,5 +16,13 @@
     "loopfunc": true,
     "bitwise": false,
 
-    "browser": true
+    "browser": true,
+
+    "globals": {
+        "describe": false,
+        "beforeEach": false,
+        "it": false,
+        "expect": false 
+    }
+
 }

package.json

@@ -27,7 +27,7 @@
     "grunt-contrib-concat": "~0.5.0",
     "grunt-contrib-cssmin": "^0.10.0",
     "grunt-contrib-jasmine": "~0.8.0",
-    "grunt-contrib-jshint": "~0.7.1",
+    "grunt-contrib-jshint": "~0.10.0",
     "grunt-contrib-uglify": "~0.4.0",
     "grunt-contrib-watch": "^0.6.1",
     "load-grunt-tasks": "~0.2.0"

spec/api.data-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 api data', function () {
     'use strict';

spec/api.focus-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 api load', function () {
     'use strict';

spec/api.grid-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 api grid', function () {
     'use strict';

spec/api.load-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 api load', function () {
     'use strict';

spec/api.zoom-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 api zoom', function () {
     'use strict';

spec/arc-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart axis', function () {
     'use strict';

spec/axis-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart axis', function () {
     'use strict';

spec/c3-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it;
 
 describe('c3', function () {
     'use strict';

spec/class-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart class', function () {
     'use strict';

spec/core-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart', function () {
     'use strict';

spec/data-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart data', function () {
     'use strict';

spec/domain-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart axis', function () {
     'use strict';

spec/grid-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart grid', function () {
     'use strict';

spec/interaction-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart interaction', function () {
     'use strict';

spec/legend-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart legend', function () {
     'use strict';

spec/shape.bar-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 var setMouseEvent = window.setMouseEvent;
 

spec/shape.line-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart shape line', function () {
     'use strict';

spec/tooltip-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    jasmine = window.jasmine,
-    beforeAll = window.beforeAll,
-    beforeEach = window.beforeEach;
+var jasmine = window.jasmine,
+    beforeAll = window.beforeAll;
 
 describe('c3 chart tooltip', function () {
     'use strict';

spec/type-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart types', function () {
     'use strict';

spec/zoom-spec.js

-var describe = window.describe,
-    expect = window.expect,
-    it = window.it,
-    beforeEach = window.beforeEach;
 
 describe('c3 chart zoom', function () {
     'use strict';