re-organize contracts

contracts/GiftBucket.sol

@@ -1,7 +1,7 @@
 pragma solidity ^0.6.1;
 pragma experimental ABIEncoderV2;
 
-import "./IERC20.sol";
+import "./erc20/IERC20.sol";
 
 contract GiftBucket {
 

contracts/GiftBucketFactory.sol

@@ -6,7 +6,7 @@ import "./Proxy.sol";
 contract GiftBucketFactory {
   GiftBucket public GiftBucketImplementation;
 
-  event Created(address indexed gifter, address indexed bucket);
+  event BucketCreated(address indexed gifter, address indexed bucket);
 
   constructor() public {
     GiftBucketImplementation = new GiftBucket(address(0), block.timestamp + 1);
@@ -14,7 +14,7 @@ contract GiftBucketFactory {
 
   function create(address _tokenAddress, uint256 _expirationTime) public returns (address) {
     address p = address(new Proxy(abi.encodeWithSelector(0xc350a1b5, _tokenAddress, _expirationTime, msg.sender), address(GiftBucketImplementation)));
-    emit Created(msg.sender, p);
+    emit BucketCreated(msg.sender, p);
     return p;
   }
 }