BUG: 0003029 force slicer to be in the C locale to avoid data truncation

Set the locale to be "C" to avoid issues related to reading and writing
of floating point numbers. For example, when the decimal point is set to be
a comma instead of a period, there can be truncation of data.
See these previous commits and the

• // http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=21856
• // http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=21865
• // http://slicer-devel.65872.n3.nabble.com/Re-Rounding-to-integer-tt4027985.html
• // http://slicer-devel.65872.n3.nabble.com/Re-slicer-users-Slicer4-can-t-really-use-it-yet-td4028040.html
• // http://slicer-users.65878.n3.nabble.com/Slicer4-DICOM-many-problems-td4025919.html
• // and issue 0003029

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22074 3bd1e089-480b-0410-8dfb-8563597acbee