ENH: Use try_run to determine of std::regex works
This MR uses CMake/CheckCXXSoureRuns.cmake to determine if there is a working version of std::regex. Some compilers amy compil and run std:;regex code, but the results are imcorrect.
If a working std::regex is not available fall back to using the less efficient kwysy::RegularExpresion.
BUG: VTK/CMake/CheckCXXSourceRuns.cmake ahd a bug that reported a successful run if the test code compiled. It never checked the return code of the code beig tested.