Fixed calculation of deposit_amount

[eorituz]

Since jacobs scenario is the first one to use balance_per_node
We never tested the calculation for depositing more tokens.

Since the UDC contract requires a deposit greater than the total_deposit

function deposit(address beneficiary, uint256 new_total_deposit)
        external
    {
        require(new_total_deposit > total_deposit[beneficiary], "deposit not increasing");

        // Calculate the actual amount of tokens that will be transferred
        uint256 added_deposit = new_total_deposit - total_deposit[beneficiary];

        balances[beneficiary] += added_deposit;
        total_deposit[beneficiary] += added_deposit;

        // Update whole_balance, but take care against overflows.
        require(whole_balance + added_deposit >= whole_balance, "overflowing deposit");
        whole_balance += added_deposit;

        // Decline deposit if the whole balance is bigger than the limit.
        require(whole_balance <= whole_balance_limit, "too much deposit");

        // Actual transfer.
        require(token.transferFrom(msg.sender, address(this), added_deposit), "tokens didn't transfer");

I needed to change the calculation of the amount that needs to be deposited

This is a fix for Issue #238

[deepbrook]

max() should not be necessary here - there should be a check^suggestion

in this class instead, that ensures that max_funding >= balance_per_node when loading the scenario yaml.

Otherwise, this would silently use a value that may not be expected by the user.

---

Suggested validation::

def validate(self):
    self.assert_option(self.max_funding < self.balance_per_node, "max_funding must be >= balance_per_node value!")

I trust you can write a test for that just fine. ;P

[deepbrook]

That would've taken me days to figure out - good catch! Just a small change required, then we're good to merge this.

[deepbrook]

Some leftovers, then you're good.

[deepbrook]

Geht doch! >:D