ENH: added cmake check for stdint.h
ENH: added cmake check for stdint.h

This is done to to get a configure error instead of a compile error
for unsupported compilers.

SimpleITK/Staging,SimpleITK/Staging,SimpleITK/Staging,SimpleITK/Staging,SimpleITK/Staging,SimpleITK/Staging,SimpleITK/Staging