STYLE: CMakeLists.txt: Set CMP0048 policy to NEW

This commit also updates projects EMSegment, MultiVolumeExplorer,
OpenIGTLinkIF and SlicerSimpleFilters.

EMSegment:

r17114
STYLE: Fix CMake warning setting CMP0048 to NEW

MultiVolumeExplorer:

$ git shortlog 9cd4730..a0743dc --no-merges
Jean-Christophe Fillion-Robin (5):
STYLE: Remove unused extension packaging code
STYLE: Simplify CMakeLists.txt removing extra comments
STYLE: Update CMakeLists.txt to use recommended variable names
STYLE: Update testing/CMakeLists.txt to use slicerMacroConfigureModuleCxxTestDriver
STYLE: Fix CMake warning setting CMP0048 to NEW

OpenIGTLinkIF:

$ git shortlog 435b1c3..3ad1f67 --no-merges
Jean-Christophe Fillion-Robin (3):
STYLE: Simplify CMakelists directly including find_package(Slicer)
STYLE: CMakeLists.txt: Use recommended variable names
STYLE: Fix CMake warning setting CMP0048 to NEW

SlicerSimpleFilters:

$ git shortlog 48b7873..c58cfe5 --no-merges
Jean-Christophe Fillion-Robin (1):
STYLE: Fix CMake warning setting CMP0048 to NEW

git-svn-id: http://svn.slicer.org/Slicer4/trunk@24777 3bd1e089-480b-0410-8dfb-8563597acbee