Rename fn_args file to nargs

Author: Luni-4

src/metrics/fn_args.rs

@@ -1,8 +1,8 @@
 pub mod cognitive;
 pub mod cyclomatic;
 pub mod exit;
-pub mod fn_args;
 pub mod halstead;
 pub mod loc;
 pub mod mi;
+pub mod nargs;
 pub mod nom;