Changed a few error() calls to log_write(). Removed the (redundant)

"\n" from a few error() calls.  Changed a few f?printf() calls to
error() or log_write().

Most notably, I didn't change any of the --interactive printf()s or
the usage printf() call.

I think we should draw up some internal notes on when to use
LOG_STDOUT versus LOG_PLAIN versus all the other LOG_* options.

main.cc

@@ -152,7 +152,7 @@ int main(int argc, char *argv[]) {
 
 #ifdef __amigaos__
 	if(!OpenLibs()) {
-		printf("Couldn't open TCP/IP Stack Library(s)!\n");
+		error("Couldn't open TCP/IP Stack Library(s)!");
 		exit(20);
 	}
 	MiamiBPFInit((struct Library *)MiamiBase, (struct Library *)SocketBase);