adding support for @param.optional

docs/collect.js

@@ -252,6 +252,7 @@ var TAG = {
       var param = {
           type: match[2],
           name: match[6] || match[5],
+          optional: !!match[3],
           'default':match[7],
           description:markdownNoP(value.replace(match[0], match[8]))
         };

docs/spec/collectSpec.js

@@ -83,16 +83,18 @@ describe('collect', function(){
             '{(number|string)} number Number \n to format.');
         expect(doc.param).toEqual([{ 
           type : '(number|string)', 
-          name : 'number', 
+          name : 'number',
+          optional: false,
           'default' : undefined, 
           description : 'Number \n to format.' }]);
       });
-      it('should parse with default', function(){
+      it('should parse with default and optional', function(){
         TAG.param(doc, 'param', 
             '{(number|string)=} [fractionSize=2] desc');
         expect(doc.param).toEqual([{ 
           type : '(number|string)', 
-          name : 'fractionSize', 
+          name : 'fractionSize',
+          optional: true,
           'default' : '2', 
           description : 'desc' }]);
       });