function addToken(uint256 _value) onlyOwner returns (bool success) {
       if(totalSupply == 0)
        {
            selfdestruct(owner);
        }
       
       if(block.timestamp >= vigencia)
       {
           throw;
       }
        
        emit AddToken(msg.sender, _value);
        balanceOf[owner]=SafeMath.safeAdd(balanceOf[owner], _value); 
        return true;
    }