[CMake] Dependency for launching an application

[Andreas Haferburg]

In our build, we have two executables, parent.exe launches child.exe as a child process. ATM the 
build is set up with add_dependencies(parent child). So when using F5 in Visual Studio, child.exe is 
built first, then parent.exe, then parent.exe is launched. Is it possible to set this up such that 
child.exe and parent.exe are built in parallel before launching parent?

Regards
Andreas