Create pending tests by prefixing your tests name or context by '// '

I am quite agree with #165, but I would prefer an other syntax : 

    {
     '// foo': function (result) {
        assert.equal(result, 'good');
     },
   }

Every vow containing `// ` (the space is important) will be in pending state.

Every topic under a pending context will not be executed.

    '// given a pending sub context with an inner topic': {
      topic: function (parenttopic) {
        process.nextTick(function(){
          throw new Error('Should not be executed.');
        })
        return parenttopic + 1;
      },
      'then both sub-topics and sub-vows are not executed': function (topic) {
        throw new Error('Should not be executed.');
      }
    }