Set the minimum required version of CMake high enough to avoid the
warning for CMAKE_LEGACY_CYGWIN_WIN32. The warning appears on stderr
and breaks the expected output matching.
When CMake reports failure to configure a project, especially when the
toolchain does not initialize properly, the true reason may be clear
from reading the CMakeFiles/CMake(Output|Error).log files. Advise users
to look at these files if they exist when configuration fails.
Add RunCMake.Configure test to check that the log files are mentioned
when configuration fails.