Add v0.5 contracts to test

contracts/A_v0dot5.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.5.2;
+
+contract A_v0dot5 {
+  uint256 a;
+
+  constructor(uint256 _a) public {
+    a = _a;
+  }
+}

contracts/SimpleStore_v0dot5.sol

@@ -0,0 +1,17 @@
+pragma solidity ^0.5.2;
+
+contract SimpleStore_v0dot5 {
+  constructor(uint _value) public {
+    value = _value;
+  }
+
+    function set(uint newValue) public {
+        value = newValue;
+    }
+
+    function get() public view returns (uint) {
+        return value;
+    }
+
+    uint value;
+}