Update README.md

Author: islamdidarmd

README.md

@@ -15,6 +15,15 @@ Just add the dependency to your *build.gradle*:
          implementation 'com.github.droidbond:LoadingButton:0.1.0'
    }
 ```
+```
+minSdk 15
+targetSdk 28
+```
+
+### Demo
+  <img src="https://github.com/droidbond/LoadingButton/blob/master/device-2018-11-22-155730.png" width="250">
+  <img src="https://github.com/droidbond/LoadingButton/blob/master/device-2018-11-22-155750.png" width="250">
+
 ### How to use
 Inside xml layout
 ```xml