Add a warning when we reach the 64 elements limit of "spot removal" module
I had to use the spot removal module on a badly dirty sensor.
I've reached a limit which is 64.
After that, the module continues to accept more entries but does not do anything.
I could finish the work opening a new instance of the module.
Can you add, please, a form of warning when the limit is reached and stop the module to "seem to work".