Added Claimable contract as an extension of Ownable with the Claimable tests

contracts/Claimable.sol

+pragma solidity ^0.4.0;
+import './Ownable.sol';
+
+/*
+ * Claimable
+ * Extension for the Ownable contract, where the ownership needs to be claimed
+ */
+
+contract Claimable is Ownable {
+  address public pendingOwner;
+
+  modifier onlyPendingOwner() {
+    if (msg.sender == pendingOwner)
+      _;
+  }
+
+  function transfer(address newOwner) onlyOwner {
+    pendingOwner = newOwner;
+  }
+
+  function claimOwnership() onlyPendingOwner {
+    owner = pendingOwner;
+    pendingOwner = 0x0;
+  }
+
+}

migrations/2_deploy_contracts.js

@@ -3,6 +3,7 @@ module.exports = function(deployer) {
   deployer.deploy(BadArrayUse);
   deployer.deploy(ProofOfExistence);
   deployer.deploy(Ownable);
+  deployer.deploy(Claimable);
   deployer.deploy(LimitFunds);
   if(deployer.network == 'test'){
     deployer.deploy(SecureTargetMock);

test/Claimable.js

+contract('Claimable', function(accounts) {
+
+  it("should have an owner", function(done) {
+    var claimable = Claimable.deployed();
+    return claimable.owner()
+      .then(function(owner) {
+        assert.isTrue(owner != 0);
+      })
+      .then(done)
+  });
+
+  it("changes pendingOwner after transfer", function(done) {
+    var claimable = Claimable.deployed();
+    return claimable.transfer(accounts[1])
+      .then(function() {
+        return claimable.pendingOwner();
+      })
+      .then(function(pendingOwner) {
+        assert.isTrue(pendingOwner === accounts[1]);
+      })
+      .then(done)
+  });
+
+  it("should prevent to claimOwnership from no pendingOwner", function(done) {
+    var claimable = Claimable.deployed();
+    return claimable.claimOwnership({from: accounts[2]})
+      .then(function() {
+        return claimable.owner();
+      })
+      .then(function(owner) {
+        assert.isTrue(owner != accounts[2]);
+      })
+      .then(done)
+  });
+
+  it("changes allow pending owner to claim ownership", function(done) {
+    var claimable = Claimable.deployed();
+    return claimable.claimOwnership({from: accounts[1]})
+      .then(function() {
+        return claimable.owner();
+      })
+      .then(function(owner) {
+        assert.isTrue(owner === accounts[1]);
+      })
+      .then(done)
+  });
+
+  it("should prevent non-owners from transfering" ,function(done) {
+    var claimable = Claimable.deployed();
+    return claimable.transfer(accounts[2], {from: accounts[2]})
+      .then(function() {
+        return claimable.pendingOwner();
+      })
+      .then(function(pendingOwner) {
+        assert.isFalse(pendingOwner === accounts[2]);
+      })
+      .then(done)
+  });
+
+});