Unity to print C-style escaped strings as "\x16"

Changes from "\0x16" before, makes it easier to copy strings from output

test/tests/testunity.c

@@ -1373,7 +1373,7 @@ void testNotEqualString4(void)
 void testNotEqualStringLen4(void)
 {
     EXPECT_ABORT_BEGIN
-    TEST_ASSERT_EQUAL_STRING_LEN("\r\x16", "bar\n", 4);
+    TEST_ASSERT_EQUAL_STRING_LEN("ba\r\x16", "ba\r\n", 4);
     VERIFY_FAILS_END
 }