Added directfs

Added a very rudimentary file I/O system suitable for experimenting
with the language further. A better one will be designed when we have
sensible error management.

src/error/mod.rs

@@ -2,7 +2,6 @@
 mod import_all;
 mod no_targets;
 mod not_exported;
-// mod not_found;
 mod conflicting_roles;
 mod parse_error_with_tokens;
 mod project_error;