From time to time there is a need to set a Functions Inventory to Limited to 0, which the App allows to save and works. However the API well then error shown below. 

We just need consistency either the API is fixed, or the App shouldn't allow the limit be 0.  

[message] => Value is not a positive number: 0

[locations] => Array

[0] => Array

(

[line] => 43

[column] => 11

)

)

[path] => Array

(

[0] => event

[1] => setup

[2] => function

[3] => functions

[4] => 12

[5] => inventoryLimit

)

[extensions] => Array

(

[code] => INTERNAL_SERVER_ERROR

))