function addContributorManually( address who, uint contributionWei, uint tokens) public returns(bool) {
        
        require(msg.sender == owner);   
        
        require(hasStarted == false);
        
        require(block.timestamp < preSale.start);
        
        require((tokensRemainingForSale + tokensAwardedForSale) == TOTAL_TOKENS_TO_DISTRIBUTE);
        
        
        preSale.tokens -= tokens;

        addContribution(who, contributionWei, tokens);
        Contribute(who, contributionWei, tokens);
        return true;
    }