Limit number of germinations to number of seeds

[jhrcook]

Currently, there can be more germinations than there were plants sown. This is a logic flaw.

The plants manager should throw an error saying that the user is trying to add too many germinations. Then the controller that is requesting the change can respond with an alert for the user.

There are two places where germinations can be added: the information view with a simple addition to the current day, and when the user is manually adding germinations to any date.