feat: swap println for eprintln or debug_eprintln

Unified expected output to always eprintln so outputs can be piped to
other processes. Added debug_eprintln and switched all occurances of
debug_println.

src/lib.rs

@@ -11,8 +11,8 @@ pub mod scripts;
 
 // NOTE: stolen from https://docs.rs/debug_print/latest/debug_print/
 #[macro_export]
-macro_rules! debug_println {
-    ($($arg:tt)*) => (if ::std::cfg!(debug_assertions) { ::std::println!($($arg)*); })
+macro_rules! debug_eprintln {
+    ($($arg:tt)*) => (#[cfg(debug_assertions)] eprintln!($($arg)*));
 }
 
 fn safe_create_file(path: PathBuf) -> Result<File, std::io::Error> {