title: Global "Text" color and "TextInput" text color
body: <p>I've started to work with react-native few days ago and after some extensive search I weren't able to find answers for 2 (simple?) questions:</p>
  
  <ol>
  <li><p>How can I change the color of ALL <strong>Text</strong> components in react-native?
  What are the best practices? Creating an own Text component with
  styling and reusing it everywhere?</p></li>
  <li><p>Change the default text color of <strong>TextInput</strong>. I managed to change the
      placeholder color, and also the underline color in android, but I
      can't find anything on how to change the input text color (stays
      black).</p></li>
  <li>Can I change the font / text color for <strong>everything</strong> anyhow? This
  option seems to be missing.</li>
  </ol>
  
  <p>Thanks for any help and cheers</p>