Update CheckDGtalDependencies.cmake

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Update CheckDGtalDependencies.cmake
Update CheckDGtalDependencies.cmake
Minor fix in Trace.ih
Merge pull request #674 from dcoeurjo/minorTrace

Minor fix in Trace.ih
CGAL in cmake  + functors + test (working on cmake bug)
Adding CGAL deps and curvature estimators
Cmake clenaup
Cleanup cmake
Fixing merge