Add budget example

web3.js/src/budget-contract.js

@@ -118,6 +118,14 @@ export class BudgetContract {
     return '4uQeVj5tqViQh7yWWGStvkEG1Zmhx6uasJtWCJziofM';
   }
 
+  /**
+   * The amount of space this contract requires
+   */
+  static get space(): number {
+    return 128;
+  }
+
+
   /**
    * Creates a timestamp condition
    */
@@ -196,7 +204,7 @@ export class BudgetContract {
 
       return new Transaction({
         fee: 0,
-        keys: [from, contract],
+        keys: [from, contract, to],
         contractId: this.contractId,
         userdata: userdata.slice(0, pos),
       });
@@ -217,7 +225,7 @@ export class BudgetContract {
 
       return new Transaction({
         fee: 0,
-        keys: [from, to],
+        keys: [from, contract, to],
         contractId: this.contractId,
         userdata: userdata.slice(0, pos),
       });

web3.js/src/index.js

@@ -2,3 +2,5 @@
 export {Account} from './account';
 export {Connection} from './connection';
 export {Transaction} from './transaction';
+export {SystemContract} from './system-contract';
+export {BudgetContract} from './budget-contract';