Preface, much of the PSAPI could be imported, but I only need one function, so I will only provide one function

Currently JNA's PSAPI is missing the QueryWorkingSetEx function. The only Type-Declarations missing would be the PSAPI_WORKING_SET_EX_INFORMATION and the PSAPI_WORKING_SET_EX_BLOCK Union Struct.

The only changes would be within the Psapi.java file.

I'll be trying to get a PR in sometime this week, just created the issue to note it down.