Compiled languages are Meson's bread and butter, but hardly required.
This is convenient, because many test caases specifically, do not care
about testing the compiler interactions.
In such cases, we can skip doing compiler lookups which aren't used, as
they only slow down test setup.
Rather than having to manually build the locale aware man paths with
`install_data('foo.fr.1', install_dir: join_paths(get_option('mandir'), 'fr', 'man1'), rename: 'foo.1')`
Support doing
`install_man('foo.fr.1', locale: 'fr')`
D lang compilers have an option -release (or similar) which turns off
asserts, contracts, and other runtime type checking. This patch wires
that up to the b_ndebug flag.
Fixes#7082