Function c2rust_transpile::build_files::emit_build_files

pub fn emit_build_files(
    tcfg: &TranspilerConfig, 
    build_dir: &Path, 
    modules: Vec<PathBuf>, 
    pragmas: IndexSet<(&'static str, &'static str)>, 
    crates: IndexSet<&'static str>
) -> Option<PathBuf>

Emit Cargo.toml and lib.rs for a library or main.rs for a binary. Returns the path to lib.rs or main.rs (or None if the output file existed already).