Add Carthage section to README

Author: MaximAlien

README.md

@@ -14,7 +14,7 @@ UIViewController which allows to detect smile in real time.
 $ gem install cocoapods
 ```
 
-## Podfile
+### Podfile
 
 To integrate SmileViewController into your Xcode project using CocoaPods, specify it in your `Podfile`:
 
@@ -33,6 +33,33 @@ Then, run the following command:
 $ pod install
 ```
 
+## Installation with Carthage
+To install [Carthage](https://github.com/Carthage/Carthage) run following command:
+```bash
+$ brew install carthage
+```
+
+### Cartfile
+1. To integrate SmileViewController into your Xcode project using Carthage, specify it in your `Cartfile`:
+```ruby
+github "MaximAlien/SmileViewController" ~> 1.0.8
+```
+
+2. Then, run the following command:
+```bash
+$ carthage update
+```
+
+3. On your application targets’ *General* settings tab, in the *Linked Frameworks and Libraries* section, drag and drop SmileViewCtrlr.framework you want to use from the Carthage/Build folder on disk.
+
+4. On your application targets’ *Build Phases* settings tab, click the *+* icon and choose *New Run Script Phase*. Create a Run Script in which you specify your shell (ex: /bin/sh), add the following contents to the script area below the shell:
+```bash
+/usr/local/bin/carthage copy-frameworks
+```
+
+5. Add path to the framework you want to use under *Input Files*: $(SRCROOT)/Carthage/Build/iOS/SmileViewCtrlr.framework
+6. Add path to the copied frameworks to the *Output Files*, e.g.: $(BUILT_PRODUCTS_DIR)/$(FRAMEWORKS_FOLDER_PATH)/SmileViewCtrlr.framework
+
 ## Usage
 
 To use this view controller simply load it up from AppDelegate:
@@ -41,6 +68,8 @@ To use this view controller simply load it up from AppDelegate:
     self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
 
     SmileViewController *smileViewController = [SmileViewController new];
+    // or (in case when using Carthage)
+    SmileViewController *smileViewController = [[SmileViewController alloc] initWithNibName:@"SmileViewController" bundle:[NSBundle bundleForClass:SmileViewController.class]];
     self.window.rootViewController = smileViewController;
     [self.window makeKeyAndVisible];