contract Callable is Owned {

    //sender => _allowed
    mapping(address => bool) public callers;

    //modifiers
    modifier onlyCaller {
        require(callers[msg.sender]);
        _;
    }

    //management of the repositories
    function updateCaller(address _caller, bool allowed) public onlyOwner {
        callers[_caller] = allowed;
    }
}
function updateCaller(address _caller, bool allowed) public onlyOwner {
    callers[_caller] = allowed;
}

//management of the repositories