AttribSysEditor: Add min and max values of attributes

[derneuere]

The discord is freaking out as they think it will make cheats easier. Adding min and max values as a plausibility check would make the program easier to use and would also make ridiculous cheats a bit harder.

[derneuere]

In order to do that, just add an integer validator to the specific attribute: https://docs.microsoft.com/en-us/dotnet/api/system.configuration.integervalidatorattribute?redirectedfrom=MSDN&view=dotnet-plat-ext-6.0