code: function shiftDeepValue(target, path) {
      var deepRef = getDeepRef(target, path);
      if (!isArray(deepRef))
          return;
      return deepRef.shift();
  }
docs: Shift a value of an array which is a deep property in an object, based on a path to that property
  
  @param   {object} target   the Object to shift the value of
  @param   {string} path     'path.to.sub.prop'
  @returns {*}               the shifted value