add --sudo flag
This adds --sudo flag to Build.PL. This flag is passed to cpanm,
so it is possible to build Slicer on linux without beeing root (build files
are owned by user)
Bugfix in utils/pdf-slices.pl, wrong shift caused slices to be outside the media box
Merge pull request #1928 from ledvinap/pull-sudo

add --sudo flag
Merge remote-tracking branch 'upstream/master'