Replace NEKit dependency with reduced subset

GlassVPN/DDLog.swift

@@ -0,0 +1,24 @@
+import Foundation
+
+// MARK: Third party dependencies
+//
+// Removed unnecessary parts of NEKit to keep the dependency chain small.
+// Omitting embeded frameworks; which aren't allowed in NetworkExtensions?
+//
+// 0.15.0 https://github.com/zhuhaow/NEKit/commit/f09ba8aef1e70881edf0578d23c04d88cc706f52
+// 0.3.0  https://github.com/zhuhaow/Resolver/commit/5d08fd52822d1f9217019ae8867e78daa48f667c
+// 7.6.4  https://github.com/robbiehanson/CocoaAsyncSocket/commit/0e00c967a010fc43ce528bd633d032f17158d393
+
+
+// MARK: DDLog
+
+#if DEBUG
+@inlinable public func DDLogVerbose(_ message: String) { NSLog("[VPN.VERBOSE] " + message) }
+@inlinable public func DDLogDebug(_ message: String) { NSLog("[VPN.DEBUG] " + message) }
+#else
+@inlinable public func DDLogVerbose(_ _: String) {}
+@inlinable public func DDLogDebug(_ _: String) {}
+#endif
+@inlinable public func DDLogInfo(_ message: String) { NSLog("[VPN.INFO] " + message) }
+@inlinable public func DDLogWarn(_ message: String) { NSLog("[VPN.WARN] " + message) }
+@inlinable public func DDLogError(_ message: String) { NSLog("[VPN.ERROR] " + message) }