If a path argument with no -S or -B leads to a cache directory,
use that directory as the binary directory. Otherwise, use the
binary directory from the preset.
Fixes: #21311
Document the previously internal option of '-B' and provide a
matching source directory option with '-S'. Both '-B', and '-S'
can be used independently of each other.
Port most CMakeTestBadCommandLines test cases to RunCMake.CommandLine
and drop the former test. Add validation of expected results, which was
not done by the old test.
Kyle Edwards