Fix datatests to be properly working in newer nightly rust

tests/datatests/mod.rs

@@ -0,0 +1,24 @@
+// This file is generated by build.rs
+
+use std::path::Path;
+use std::fs::File;
+use std::io::Read;
+use super::common::TestCase;
+use super::get_library;
+
+fn integration_tests(input: &Path) {
+    let mut str: String = "".to_string();
+    let mut file = File::open(input).unwrap();
+    file.read_to_string(&mut str).unwrap();
+    let test_case = serde_yaml::from_str::<TestCase>(&str).unwrap();
+    println!("	Running integration test {}", test_case.name);
+    test_case.run_test(get_library());
+}
+
+
+#[test]
+fn basic_single_turn() {
+    integration_tests(Path::new("tests/test_cases/basic_single_turn.yaml"));
+}
+
+