1. In the review panel of the druid, the first transaction is incorrect.
The second should be the first and the third should be the second and so on.

2. There are n+1 payments listed for an n-month loan

3. Both 1 and 2 also occur in the created sched transaction.

4. The sched transaction creator makes the first repayment date the 'last
made payment' of the sched xaction. This means that the first repayment
won't happen until one month later.

5. If you use the druid to pick up in the middle of an existing loan (e.g.
12 payments have already been made), the first one the sched xaction
creator will make is the 12th, not the 13th

Resolution: All of these were caused by recurring off-by-one errors in
druid-loan.c. Patch attached.