BUG: Fix typos in globalIndexNames.

Reported by Jan Ehrhardt (ehrhardt@imi.uni-luebeck.de): The bug results in
JoinSeriesImageFilter failures when more than 71 input images are used.

Change-Id: I3c548ed3c0af70fdbad30ecf916d57011976bd8c
Merge branch 'release'

Change-Id: I0a21608a6b293706cf3696537b4ab60056f69401