-[SSYAlert init] now NSLogs and returns nil if called from a non-main thread.

Author: jerrykrinock

SSYAlert.m

@@ -2297,15 +2297,25 @@ - (NSControlStateValue)checkboxState {
 // bottom of the menu bar.
 
 - (id)init {
+    BOOL ok = YES;
+    
     /* See Note ActivationPolicy. */
 	if (!NSApp || ([NSApp activationPolicy] == NSApplicationActivationPolicyProhibited)) {
+        ok = NO;
+	}
 
+    if (![[NSThread currentThread] isMainThread]) {
+        NSLog(@"Failing attempt to init SSYAlert on non-main thread");
+        ok = NO;
+    }
+    
+    if (!ok) {
 #if !__has_feature(objc_arc)
-		[super dealloc] ;
+        [super dealloc] ;
 #endif
-		return nil ;
-	}
-	
+        return nil ;
+    }
+    
 	// Create window
 	NSRect initialRect = NSMakeRect(0, 0, WINDOW_PROTOTYPE_WIDTH, WINDOW_PROTOTYPE_HEIGHT) ;
 	// WINDOW_PROTOTYPE_WIDTH is because: If I use NSZeroRect, [window center] places