add support for storing git tag

Author: ghedamat

lib/scm-data-generators/git.js

@@ -18,7 +18,8 @@ module.exports = CoreObject.extend({
           email: info.author_email.substring(0, info.author_email.length - 1),
           name: info.author_name,
           timestamp: new Date(info.date).toISOString(),
-          branch: gitRepoInfo().branch
+          branch: gitRepoInfo().branch,
+          tag: gitRepoInfo().tag
         });
       });
     });

tests/unit/lib/scm-data-generators/git-nodetest.js

@@ -32,6 +32,7 @@ describe('the git scm data generator', function() {
           assert.equal(data.name, 'Alisdair McDiarmid');
           assert.isNotNull(data.timestamp);
           assert.equal(data.branch, 'master');
+          assert.equal(data.tag, '2.3.4');
         });
     });
   });