errors now write to stderr instead of stdout

src/error.rs

@@ -1,24 +1,24 @@
 use std::process::exit;
 
 pub fn unmatched_flag(target: String) {
-	println!("pride: no flag {target}");
+	eprintln!("pride: no flag {target}");
 	exit(1);
 }
 
 
 pub fn size_missing() {
-	println!("pride: size flag requires a value");
+	eprintln!("pride: size flag requires a value");
 	exit(2);
 }
 
 pub fn size_error(value: &str) {
-	println!("pride: size '{value}' is invalid");
+	eprintln!("pride: size '{value}' is invalid");
 	exit(2);
 }
 
 
 pub fn too_small(width: u16, height: u16) {
-	println!("pride: this flag must be bigger than {width}x{height}");
+	eprintln!("pride: this flag must be bigger than {width}x{height}");
 	exit(3);
 }