Revert "add workaround because truffle doesn't support transitive dependencies"

This reverts commit 48a7cd4e.

contracts/access/SignatureBouncer.sol

 pragma solidity ^0.4.18;
 
-import "../zos-lib/migrations/Migratable.sol";
 import "../ownership/Ownable.sol";
 import "../ownership/rbac/RBAC.sol";
 import "../ECRecovery.sol";
 
-
 /**
  * @title SignatureBouncer
  * @author PhABC and Shrugs

contracts/ownership/Ownable.sol

 pragma solidity ^0.4.21;
 
-import "../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 
 
 /**

contracts/ownership/rbac/RBACWithAdmin.sol

 pragma solidity ^0.4.21;
 
 import "./RBAC.sol";
-import "../../zos-lib/migrations/Migratable.sol";
-
+import 'zos-lib/contracts/migrations/Migratable.sol';
 
 /**
  * @title RBACWithAdmin

contracts/payment/SplitPayment.sol

 pragma solidity ^0.4.21;
 
 import "../math/SafeMath.sol";
-import "../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 
 
 /**

contracts/token/ERC20/DetailedERC20.sol

 pragma solidity ^0.4.21;
 
 import "./ERC20.sol";
-import "../../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 
 
 contract DetailedERC20 is Migratable, ERC20 {

contracts/token/ERC20/DetailedMintableToken.sol

 pragma solidity ^0.4.21;
 
-import "../../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 import "./DetailedERC20.sol";
 import "./MintableToken.sol";
 

contracts/token/ERC20/DetailedPremintedToken.sol

 pragma solidity ^0.4.21;
 
-import "../../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 import "./DetailedERC20.sol";
 import "./MintableToken.sol";
 

contracts/token/ERC20/MintableToken.sol

@@ -2,7 +2,7 @@ pragma solidity ^0.4.21;
 
 import "./StandardToken.sol";
 import "../../ownership/Ownable.sol";
-import "../../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 
 
 /**

contracts/token/ERC20/TokenTimelock.sol

 pragma solidity ^0.4.21;
 
 import "./SafeERC20.sol";
-import "../../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 
 
 /**

contracts/token/ERC20/TokenVesting.sol

@@ -6,7 +6,7 @@ import "./ERC20Basic.sol";
 import "./SafeERC20.sol";
 import "../../ownership/Ownable.sol";
 import "../../math/SafeMath.sol";
-import "../../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 
 
 /**

contracts/token/ERC721/ERC721Token.sol

@@ -2,7 +2,7 @@ pragma solidity ^0.4.21;
 
 import "./ERC721.sol";
 import "./ERC721BasicToken.sol";
-import "../../zos-lib/migrations/Migratable.sol";
+import "zos-lib/contracts/migrations/Migratable.sol";
 
 
 /**

contracts/zos-lib/migrations/Migratable.sol

-../../../node_modules/zos-lib/contracts/migrations/Migratable.sol
\ No newline at end of file