UseITK upstream issue: ITK is added to the global include path

[rijobro]

I've created an issue on ITK (InsightSoftwareConsortium/ITK#1450) flagging up the use of include_directories and link_directories in UseITK.cmake.

Can't imagine it'll be a quick fix (if at all), but we'll see what they say.

[KrisThielemans]

This can cause problems for SIRF etc or others who include STIR via CMake as the ITK include directory is therefore added to the global include path

STIR/src/cmake/STIRConfig.cmake.in

Line 82 in 6417022

include(${ITK_USE_FILE})

Internally, we don't mind that the ITK include path added for all files (currently anyway).

However, it turns out that we don't need include(${ITK_USE_FILE}) in STIRConfig.cmake (see #1518). While InsightSoftwareConsortium/ITK#1450 suggests some ways to circumvent the ITK_USE_FILE problem, updating STIRConfig.cmake solves most problems, so I won't fix this.