BUILD: Fix errors with GCC + use lkt_assert and not assert to be sure to have asserts... (diff between assert and assume?)

RUST: Place the target folder of all rust sub-projects in the rust folder to share compilation artifacts

BUILD: Remove some warnings because it won't compile with Clang/LLVM 14 => some C99 compat things + float to double conversions in SDL2

Kubat a rédigé 3 years ago et Elliu a validé 3 years ago

/!\ Not tested for the moment, do only minor compiler driven refactor /!\

The user can now `make install` or `ninja install` after the project was
build. It will install the `lektord`, `lkt` and `luka` binaries and also
install all the generated manpages into `${INSTALL_PREFIX}/man/man1`
because the manpages are about commands (category 1).

+ Also abort when reaching the to be implemented section to filter karas
to update in the repo module

BUILD: Don't abort on unknown clang option (for options available on latter versions, but CI is using an older one)