Removed old Code. Added simple plugin system

Signed-off-by: michael starke <michael.starke@hicknhack-software.com>

MacPass/MPPlugin.h

@@ -0,0 +1,37 @@
+//
+//  MPPlugin.h
+//  MacPass
+//
+//  Created by Michael Starke on 11/11/15.
+//  Copyright © 2015 HicknHack Software GmbH. All rights reserved.
+//
+
+#import <Cocoa/Cocoa.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class MPPluginManager;
+
+FOUNDATION_EXPORT NSString *const kMPPluginFileExtension;
+
+@interface MPPlugin : NSObject
+
+@property (copy, readonly) NSString *identifier;
+@property (copy, readonly) NSString *name;
+@property (copy, readonly) NSString *version;
+
+
++ (instancetype)pluginWithBundleURL:(NSURL *)url pluginManager:(MPPluginManager *)manager;
+- (instancetype)initWithPluginManager:(MPPluginManager *)manager NS_DESIGNATED_INITIALIZER;
+- (instancetype)init NS_UNAVAILABLE;
+
+@end
+
+@protocol MPPluginSettings <NSObject>
+
+@required
+@property (strong, readonly) NSViewController *settingsViewController;
+
+@end
+
+NS_ASSUME_NONNULL_END