Add Panic Button UI.

Evergreen/MainWindow/PanicButton/PanicButtonWindowController.swift

@@ -0,0 +1,43 @@
+//
+//  PanicButtonWindowController.swift
+//  Evergreen
+//
+//  Created by Brent Simmons on 11/16/17.
+//  Copyright © 2017 Ranchero Software. All rights reserved.
+//
+
+import Cocoa
+
+final class PanicButtonWindowController: NSWindowController {
+
+	var hostWindow: NSWindow?
+
+	convenience init() {
+
+		self.init(windowNibName: NSNib.Name(rawValue: "PanicButtonWindow"))
+	}
+
+	func runSheetOnWindow(_ w: NSWindow) {
+
+		hostWindow = w
+		hostWindow!.beginSheet(window!) { (returnCode: NSApplication.ModalResponse) -> Void in
+		}
+	}
+
+	private func closeSheet(_ response: NSApplication.ModalResponse) {
+
+		hostWindow!.endSheet(window!, returnCode: response)
+	}
+
+	// MARK: - Actions
+
+	@IBAction func cancel(_ sender: AnyObject) {
+
+		closeSheet(.cancel)
+	}
+
+	@IBAction func performPanic(_ sender: AnyObject) {
+
+		closeSheet(.OK)
+	}
+}