Development Wiki needs updating

[breadoven]

The development Wiki seems to be out of date at least for Ubuntu 20.04:

"make -jnproc companion28" doesn't work, "make -jnproc companion" does work though even though the final file is still called companion28.

./companion28 and ./simulator28 don't work from the build directory. They only work if you cd to the "native" directory in the build directory.

[raphaelcoeffic]

Thx, we should probably have a meta target without the version number, that should make it simpler.