Add standard library types to exercises suite

info.toml

@@ -196,4 +196,18 @@ mode = "test"
 
 [[exercises]]
 path = "exercises/threads/threads1.rs"
-mode = "compile"
+mode = "compile"
+
+# STANDARD LIBRARY TYPES
+
+[[exercises]]
+path = "exercises/standard_library_types/arc1.rs"
+mode = "compile"
+
+[[exercises]]
+path = "exercises/standard_library_types/iterator3.rs"
+mode = "test"
+
+[[exercises]]
+path = "exercises/standard_library_types/iterators4.rs"
+mode = "test"