Print non-printable characters using caret notation (#2443)

When the new flag is set, non-printable characters are printed using caret notation.

tests/integration_tests.rs

@@ -1623,6 +1623,17 @@ fn show_all_extends_tab_markers_to_next_tabstop_width_8() {
         );
 }
 
+#[test]
+fn show_all_with_caret_notation() {
+    bat()
+        .arg("--show-all")
+        .arg("--nonprintable-notation=caret")
+        .arg("nonprintable.txt")
+        .assert()
+        .stdout("hello·world^J\n├──┤^M^@^G^H^[")
+        .stderr("");
+}
+
 #[test]
 fn no_paging_arg() {
     bat()