Create Rewarder instance within ConributionRewardExt init function

contracts/controller/Controller.sol

@@ -329,7 +329,8 @@ contract Controller is Initializable {
     onlyUpgradingScheme
     returns(bool)
     {
-        require(newController == address(0), "this controller was already upgraded");   // so the upgrade could be done once for a contract.
+        // make sure upgrade could be done once for a contract.
+        require(newController == address(0), "this controller was already upgraded");
         require(_newController != address(0), "new controller cannot be 0");
         newController = _newController;
         avatar.transferOwnership(_newController);
@@ -340,7 +341,8 @@ contract Controller is Initializable {
         }
         if (nativeReputation.owner() == address(this)) {
             nativeReputation.transferOwnership(_newController);
-            require(nativeReputation.owner() == _newController, "failed to transfer reputation ownership to the new controller");
+            require(nativeReputation.owner() == _newController,
+            "failed to transfer reputation ownership to the new controller");
         }
         emit UpgradeController(address(this), newController);
         return true;

contracts/schemes/Competition.sol

@@ -3,7 +3,7 @@ pragma solidity 0.5.17;
 import "./ContributionRewardExt.sol";
 
 
-contract Competition is Initializable {
+contract Competition is Initializable, Rewarder {
     using SafeMath for uint256;
 
     uint256 constant public MAX_NUMBER_OF_WINNERS = 100;

contracts/schemes/ContributionRewardExt.sol

@@ -1,6 +1,13 @@
 pragma solidity 0.5.17;
 
 import "../votingMachines/VotingMachineCallbacks.sol";
+import "../utils/DAOFactory.sol";
+
+
+interface Rewarder {
+    function initialize(address payable) external;
+}
+
 
 /**
  * @title A scheme for proposing and rewarding contributions to an organization
@@ -81,23 +88,34 @@ contract ContributionRewardExt is VotingMachineCallbacks, ProposalExecuteInterfa
      * @param _votingParams genesisProtocol parameters - valid only if _voteParamsHash is zero
      * @param _voteOnBehalf genesisProtocol parameter - valid only if _voteParamsHash is zero
      * @param _voteParamsHash voting machine parameters
-     * @param _rewarder an address which allowed to redeem the contribution.
-       if _rewarder is 0 this param is agnored.
+     * @param _daoFactory DAOFactory instance to instance a rewarder.
+     * if _daoFactory is zero so no rewarder will be set.
+     * @param _packageVersion packageVersion to instance the rewarder from.
+     * @param _rewarderName the rewarder contract name.
+
      */
     function initialize(
         Avatar _avatar,
         IntVoteInterface _votingMachine,
         uint[11] calldata _votingParams,
         address _voteOnBehalf,
         bytes32 _voteParamsHash,
-        address _rewarder
+        DAOFactory _daoFactory,
+        uint64[3] calldata _packageVersion,
+        string calldata _rewarderName
     )
     external
     {
         super._initializeGovernance(_avatar, _votingMachine, _voteParamsHash, _votingParams, _voteOnBehalf);
-        rewarder = _rewarder;
         vault = new Vault();
         vault.initialize(address(this));
+        if (_daoFactory != DAOFactory(0)) {
+            rewarder = address(_daoFactory.createInstance(
+                                _packageVersion,
+                                _rewarderName,
+                                address(avatar),
+                                abi.encodeWithSignature("initialize(address)", address(this))));
+        }
     }
 
     /**

contracts/test/RewarderMock.sol

@@ -0,0 +1,32 @@
+pragma solidity ^0.5.17;
+
+import "../schemes/ContributionRewardExt.sol";
+
+
+contract RewarderMock is Rewarder {
+    ContributionRewardExt public contributionRewardExt;
+
+    function initialize(address payable _contributionRewardExt) external {
+        contributionRewardExt = ContributionRewardExt(_contributionRewardExt);
+    }
+
+    function redeemEtherByRewarder(bytes32 _proposalId, address payable _beneficiary, uint256 _amount)
+    public {
+        contributionRewardExt.redeemEtherByRewarder(_proposalId, _beneficiary, _amount);
+    }
+
+    function redeemNativeTokenByRewarder(bytes32 _proposalId, address payable _beneficiary, uint256 _amount)
+    public {
+        contributionRewardExt.redeemNativeTokenByRewarder(_proposalId, _beneficiary, _amount);
+    }
+
+    function redeemExternalTokenByRewarder(bytes32 _proposalId, address payable _beneficiary, uint256 _amount)
+    public {
+        contributionRewardExt.redeemExternalTokenByRewarder(_proposalId, _beneficiary, _amount);
+    }
+
+    function redeemReputationByRewarder(bytes32 _proposalId, address payable _beneficiary, uint256 _amount)
+    public {
+        contributionRewardExt.redeemReputationByRewarder(_proposalId, _beneficiary, _amount);
+    }
+}