added readonly to docs for type property, closes #235

Author: liabru

src/body/Body.js

@@ -673,6 +673,7 @@ var Axes = require('../geometry/Axes');
      * @property type
      * @type string
      * @default "body"
+     * @readOnly
      */
 
     /**

src/body/Composite.js

@@ -596,6 +596,7 @@ var Body = require('./Body');
      * @property type
      * @type string
      * @default "composite"
+     * @readOnly
      */
 
     /**

src/constraint/Constraint.js

@@ -297,6 +297,7 @@ var Common = require('../core/Common');
      * @property type
      * @type string
      * @default "constraint"
+     * @readOnly
      */
 
     /**

src/constraint/MouseConstraint.js

@@ -220,6 +220,7 @@ var Bounds = require('../geometry/Bounds');
      * @property type
      * @type string
      * @default "constraint"
+     * @readOnly
      */
 
     /**