Update README.md

Author: Fabio Tacke

README.md

@@ -3,6 +3,28 @@
 HMAC-based Extract-and-Expand Key Derivation Function (HKDF) as defined in <a href="https://tools.ietf.org/html/rfc5869">RFC 5869</a>.
 The HMAC is provided by libsodium which uses the HMAC-SHA-512/256 algorithm.
 
+## Installation
+
+### Jitpack
+To integrate the library via jitpack add the jitpack repository to your root `build.gradle` file:
+
+```
+allprojects {
+  repositories {
+    ...
+    maven { url 'https://jitpack.io' }
+  }
+}
+```
+
+You can then add the dependency to your app's `build.gradle` file where `$VERSION` specifies the specific version of the library:
+
+```
+dependencies {
+  implementation 'com.github.TICESoftware:AndroidHKDF:$VERSION'
+}
+ ```
+
 ## Usage
 For deriving a new key of length 32 bytes from some input keying material `ikm`: