old_contents: //http://solidity.readthedocs.org/en/latest/introduction-to-smart-contracts.html
  contract SimpleStorage {
      uint storedData;
      function set(uint x) {
          storedData = x;
      }
      function get() constant returns (uint retVal) {
          return storedData;
      }
  }
  
new_contents: //http://solidity.readthedocs.org/en/latest/introduction-to-smart-contracts.html
  contract SimpleStorage {
      uint storedData;
      function set(uint x) {
          storedData = x;
      }
      function get() constant returns (uint retVal) {
          return storedData;
      }
  }
  
  // Think of uint storedData as slot in database
  // Owning contract can get and set the value
  
  // allows anyone to store a single number that is accessible by anyone and writable by anyone
  
subject: Update simple.js