Since utility targets have no main output files like executables or
libraries, they do not define an output directory. This removes a call
to cmTarget::GetDirectory from cmLocalVisualStudio{6,7}Generator for
such targets.
add_custom_target() as COMMAND, and cmake will recognize them and replace
them with the actual output path of these executables. Also the dependency
will be added automatically. Test included.
ENH: moved TraceVSDependencies() to the end of GlobalGenerator::Configure(),
so it is done now in one central place
Alex