macOS API calls must be thread safe

Per hidapi, macOS HID API calls MUST be executed on the same thread to be safe:

Currently, separate threads interacting with a HID devices on macOS, the entire JVM will crash. This can actually be caused by same-thread execution due to this automatic shutdown hook.

#37
Workaround: qzind/tray@5e45845

hid4java/src/main/java/org/hid4java/HidServices.java

Lines 90 to 99 in 672f0a7

    
           if (hidServicesSpecification.isAutoShutdown()) { 
        
             // Ensure we release resources during shutdown 
        
             Runtime.getRuntime().addShutdownHook( 
        
               new Thread() { 
        
                 @Override 
        
                 public void run() { 
        
                   shutdown(); 
        
                 } 
        
               }); 
        
           }

Despite this being an upstream issue, Java has some ways of thread pooling so that we can manage this downstream until upstream has a permanent fix.

@Vzor- will be submitting a PR which references this issue with a proposed downstream threading solution.

	if (hidServicesSpecification.isAutoShutdown()) {
	// Ensure we release resources during shutdown
	Runtime.getRuntime().addShutdownHook(
	new Thread() {
	@Override
	public void run() {
	shutdown();
	}
	});
	}