Allow max in equations

[harper-wavra]

Sometimes some of the higher-percentage duration flows monthly low flows return negative values. We've had this happen a few times in the past, and were able to fix it by adding a "max" function to the equation, such that it will display the maximum of either zero, or the equation results.

When equations with the max function get sent to our services the services are not sure what max means or relates to, so it errors out and sends the error back to the client.

Client Input
Database Input