fix(extension): init extension from factory (#527)

* The initialization of the extension should be done within the same transaction that creates the extension, that prevents malicious users from calling extension.initialize before it gets added to the DaoRegistry.sol.
* All the extension factories were updated to initialize the extensions, and the extensions were updated to allow the any function call to happen during the initialization phase.
* Added more tests for Factories and DaoRegistry
* Reorganized DaoRegistry code, and updated the init function to save the dao payer at index 2 instead of 1. Index 1 will be used for the dao owner/creator.
* Removed the extension.initialize call from registry
* Updated Managing adapter

contracts/adapters/Managing.sol

@@ -166,10 +166,7 @@ contract ManagingContract is IManaging, AdapterGuard, Reimbursable {
         if (proposal.adapterOrExtensionAddr != address(0x0)) {
             dao.addExtension(
                 proposal.adapterOrExtensionId,
-                IExtension(proposal.adapterOrExtensionAddr),
-                // The creator of the extension must be set as the DAO owner,
-                // which is stored at index 0 in the members storage.
-                dao.getMemberAddress(0)
+                IExtension(proposal.adapterOrExtensionAddr)
             );
         }
     }