Add support for Apple Silicon

-Update classes to read correct Apple Silicon CPU sensor
-Update project to compile a Universal 2 binary. Upgraded Sparkle to 2.1.0 as that was the latest and supports ARM64.
-Add MacBookPro18,1 to Machines.plist

Sparkle.framework/Versions/B/Headers/SPUDownloadData.h

@@ -0,0 +1,59 @@
+//
+//  SPUDownloadData.h
+//  Sparkle
+//
+//  Created by Mayur Pawashe on 8/10/16.
+//  Copyright © 2016 Sparkle Project. All rights reserved.
+//
+
+#if __has_feature(modules)
+#if __has_warning("-Watimport-in-framework-header")
+#pragma clang diagnostic ignored "-Watimport-in-framework-header"
+#endif
+@import Foundation;
+#else
+#import <Foundation/Foundation.h>
+#endif
+
+#ifdef BUILDING_SPARKLE_DOWNLOADER_SERVICE
+// Ignore incorrect warning
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wquoted-include-in-framework-header"
+#import "SUExport.h"
+#pragma clang diagnostic pop
+#else
+#import <Sparkle/SUExport.h>
+#endif
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * A class for containing downloaded data along with some information about it.
+ */
+SU_EXPORT @interface SPUDownloadData : NSObject <NSSecureCoding>
+
+/**
+ * The raw data that was downloaded.
+ */
+@property (nonatomic, readonly) NSData *data;
+
+/**
+ * The URL that was fetched from.
+ *
+ * This may be different from the URL in the request if there were redirects involved.
+ */
+@property (nonatomic, readonly, copy) NSURL *URL;
+
+/**
+ * The IANA charset encoding name if available. Eg: "utf-8"
+ */
+@property (nonatomic, readonly, nullable, copy) NSString *textEncodingName;
+
+/**
+ * The MIME type if available. Eg: "text/plain"
+ */
+@property (nonatomic, readonly, nullable, copy) NSString *MIMEType;
+
+@end
+
+NS_ASSUME_NONNULL_END