Updated readme

LICENSE

@@ -0,0 +1,11 @@
+Copyright (C) 2020 Vladislav Vrublevsky <agins.main@gmail.com>
+This software is provided 'as-is', without any express or implied warranty.
+
+In no event will the authors be held liable for any damages arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions:
+
+- The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation is required.
+- Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+- This notice may not be removed or altered from any source or binary distribution.
+- Redistributions of any form whatsoever must retain the following acknowledgment: 'This product includes software developed by the "Vladislav Vrublevsky" (AginSquash).'

README.md

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 # GAuthDecrypt
-
+[![Latest Release](https://img.shields.io/github/v/release/AginSquash/GAuthDecrypt)](https://github.com/AginSquash/open2fa/releases)
+![Swift Version](https://img.shields.io/badge/Swift-5.0-orange.svg)
+[![Platform](https://img.shields.io/badge/platform-ios%20%7C%20macos%20%7C%20watchos%20%7C%20tvos-lightgrey)](http://cocoapods.org/pods/SwiftOTP)
+
+GAuthDecrypt is Swift library for extraction two-factor authentication secret keys from export QR codes of Google Authenticator app. At the input is a string read from a qr code, at the output is an array of objects of the GAuthOTP type. 
+I used it on my 2FA app check it [Open2FA](https://github.com/AginSquash/open2fa/)
+
+## Installation
+You can use Swift Package Manager and specify dependency in `Package.swift` by adding this:
+
+```swift
+dependencies: [
+    .package(url: "https://github.com/AginSquash/GAuthDecrypt.git", .upToNextMinor(from: "2.0.0"))
+]
+```
+
+Or click File -> Add Packages. In search form enter `https://github.com/AginSquash/GAuthDecrypt.git` and click "Copy Dependency" button.
+
+## Usage
+```swift
+let stringFromGoogleAuthApp = "otpauth-migration://offline?data=CjEKCkhlbGxvId6tvu8SGEV4YW1wbGU6YWxpY2VAZ29vZ2xlLmNvbRoHRXhhbXBsZTAC"
+let decrypted = GAuthDecryptFrom(input: stringFromGoogleAuthApp) // decrypted type is Optional<[GAuthOTP]>
+print(decrypted![0]) 
+/*
+    type: .totp, 
+    algorithm: .unspecified, 
+    name: "Example:alice@google.com", 
+    secret: "JBSWY3DPEHPK3PXP", 
+    issuer: "Example", 
+    counter: 0, 
+    digitsRawValue: 0) 
+*/
+```
+## Dependencies
+All dependencies in this project are added through SPM. Links to them:
+- https://github.com/apple/swift-protobuf
+- https://github.com/norio-nomura/Base32
+
+## License
+
+Copyright (C) 2020 Vladislav Vrublevsky <agins.main@gmail.com>
+
+This software is provided 'as-is', without any express or implied warranty.
+
+In no event will the authors be held liable for any damages arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions:
+
+- The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation is required.
+- Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+- This notice may not be removed or altered from any source or binary distribution.
+- Redistributions of any form whatsoever must retain the following acknowledgment: 'This product includes software developed by the "Vladislav Vrublevsky" (AginSquash).'