\powerChords produces superscript 5 that is too large

[Greg Swinford]

> I'm not top posting.

\version "2.14.2"

newPowerChordSymbol = {
  <c g>-\markup { \super "5" }
}

chExceptions = #( append
  ( sequential-music-to-chord-exceptions newPowerChordSymbol #t)
  ignatzekExceptions)

music = \chordmode {c:7 c:1.5 c:sus4}

\new ChordNames \chordmode {
% the 5 is currently much bigger than the 7 or sus4
  \powerChords \music
% it should match the size of the other numbers
  \set chordNameExceptions = #chExceptions \music
}