title: Including a dependency in Android Studio gives UnsatisfiedLinkError
body: <p>I am fairly new to Android programming and am trying to use the libsodium-jni library for some basic Crypto tasks. In Android Studio I add libsodium-jni-aar as a Library Dependency and I can see that this modifies my build.gradle file by adding :</p>
  
  <pre><code>compile 'com.github.joshjdevl.libsodiumjni:libsodium-jni-aar:1.0.6'
  </code></pre>
  
  <p>Many of the functions in this library work fine, but when I use the Sodium.sodium_init() function I get </p>
  
  <pre><code>java.lang.UnsatisfiedLinkError: No implementation found for int org.libsodium.jni.SodiumJNI.sodium_init() (tried Java_org_libsodium_jni_SodiumJNI_sodium_1init and Java_org_libsodium_jni_SodiumJNI_sodium_1init__)
                                                                      at org.libsodium.jni.SodiumJNI.sodium_init(Native Method)
  </code></pre>
  
  <p>I'm guessing somehow this is caused by the fact that sodium_init is a native function and for some reason the implementation is not being installed to the phone (or emulator) by gradle.</p>
  
  <p>Any help would be greatly appreciated.</p>