Dealing with multiple swift files : hello.swift and world.swift

[afabri]

When using more than one swift file to build the executable hello., one of them must be called main.swift.
It might make sense to. have that as a seprarate example, or just telling it in the readme.

[afabri]

Adding a swift file to 2_executable_library/lib/CMakeLists.txt. works without any change.

[lrineau]

I have tested locally on Linux. Looks good to me, once the two typos are fixed (missing ! and extra trailing ).

I have reservations: I wonder if it would makes sense to have a extra sub-directory, like:

  1_single_executable/
  1_bis_single_executable_multiple_swift_files/