edited BaseReporter's specFailure method to indent nested describe output

If the spec has nested describes, apply indendation.

    PhantomJS 1.9 (Mac)
     ∟ angular.equals
      ∟ when supplied two values
       ∟ where the values do not match
            Expected null not to equal {}.

Otherwise render on a single line.

    PhantomJS 1.9 (Mac) AppCtrl augments $scope with an expected API FAILED
            Expected undefined to be object.