chore: remove .cargo, add example to sys

chore(sys): bump cc

chore: ignore bindings.rs

chore(sys): compile bindings to the manifest dir too

fix(rt): resolve linker error

chore(lib, rt): add todo, and config.toml

feat(sys): use rustified enums and add config.toml

fix: use correct category names

chore(sys): exclude submodule

chore(rt): add readme

chore: distribute license

chore: add readmes, make lib no_std

chore: add metadata

fix(rt): use v0.1.0

chore(lib): init neorv32 lib