Add Rust target

spec/test_user_terminate.rs

@@ -0,0 +1,12 @@
+use testparser::*;
+
+fn main() {
+    let mut c = p_context_new(b"aacc");
+    assert_eq!(P_SUCCESS, p_parse(&mut c));
+    p_context_delete(c);
+
+    let mut c = p_context_new(b"abc");
+    assert_eq!(P_USER_TERMINATED, p_parse(&mut c));
+    assert_eq!(4200, p_user_terminate_code(&c));
+    p_context_delete(c);
+}