title: tess-two can't find libpng.so
body: <p>I have followed building instructions for tess-two on
  <a href="https://github.com/rmtheis/tess-two#build" rel="nofollow">Github</a></p>
  
  <p>I build tess-two using NDK successfully and imported the library
  I am trying to run the test application provided on the same repository but whenever the application starts it gives the following exception:
  That  error is caused once <code>new TessBaseAPI();</code> is called. </p>
  
  <pre><code>dlopen("/data/app-lib/com.datumdroid.android.ocr.simple-2/liblept.so") failed: Cannot load library: soinfo_link_image(linker.cpp:1635): could not load library "libpng.so" needed by "liblept.so"; caused by load_library(linker.cpp:745): library "libpng.so" not found
  </code></pre>
  
  <p>Can anyone help with that?</p>