Update CloudKit Support

* Update CloudKit support functionality
* Add support for app groups

Author: FahimF

Bridging-Header.h

@@ -7,4 +7,3 @@
 //
 
 #import "sqlite3.h"
-#import <time.h>

CKError-Extras.swift

@@ -0,0 +1,75 @@
+//
+//  CKError-Extras.swift
+//  SQLiteDB
+//
+//  Created by Fahim Farook on 23-10-2020.
+//  Copyright © 2020 RookSoft Ltd. All rights reserved.
+//
+
+import CloudKit
+
+extension CKError {
+	public func isRecordNotFound() -> Bool {
+		isZoneNotFound() || isUnknownItem()
+	}
+
+	public func isZoneNotFound() -> Bool {
+		isSpecificErrorCode(code: .zoneNotFound)
+	}
+
+	public func isUnknownItem() -> Bool {
+		isSpecificErrorCode(code: .unknownItem)
+	}
+
+	public func isConflict() -> Bool {
+		isSpecificErrorCode(code: .serverRecordChanged)
+	}
+
+	public func isSpecificErrorCode(code: CKError.Code) -> Bool {
+		var match = false
+		if self.code == code {
+			match = true
+		} else if self.code == .partialFailure {
+			// This is a multiple-issue error. Check the underlying array
+			// of errors to see if it contains a match for the error in question.
+			guard let errors = partialErrorsByItemID else {
+				return false
+			}
+			for (_, error) in errors {
+				if let cke = error as? CKError {
+					if cke.code == code {
+						match = true
+						break
+					}
+				}
+			}
+		}
+		return match
+	}
+
+	// ServerRecordChanged errors contain the CKRecord information
+	// for the change that failed, allowing the client to decide
+	// upon the best course of action in performing a merge.
+	public func getMergeRecords() -> (CKRecord?, CKRecord?) {
+		if code == .serverRecordChanged {
+			// This is the direct case of a simple serverRecordChanged Error.
+			return (clientRecord, serverRecord)
+		}
+		guard code == .partialFailure else {
+			return (nil, nil)
+		}
+		guard let errors = partialErrorsByItemID else {
+			return (nil, nil)
+		}
+		for (_, error) in errors {
+			if let cke = error as? CKError {
+				if cke.code == .serverRecordChanged {
+					// This is the case of a serverRecordChanged Error
+					// contained within a multi-error PartialFailure Error.
+					return cke.getMergeRecords()
+				}
+			}
+		}
+		return (nil, nil)
+	}
+}