Initial commit: add .gitignore and README

smart_contracts/contracts/SimpleStorage.sol

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.10;
+
+contract SimpleStorage {
+  uint public storedData;
+  event stored(address _to, uint _amount);
+  constructor(uint initVal) {
+    emit stored(msg.sender, initVal);
+    storedData = initVal;
+  }
+  function set(uint x) public {
+    emit stored(msg.sender, x);
+    storedData = x;
+  }
+  function get() view public returns (uint retVal) {
+    return storedData;
+  }
+}