title: Botbuilder how to use default locale strings in case namespace hasn't defined it
body: <p>I am using the botbuilder framework. I have defined several namespaces for the dialogs I have created, such as <code>help</code> or <code>default</code>. For all of these I have also created json files in my <code>locale/en/</code> directory, and all is well.
  However, I have a few sentences that are very common, and I don't feel like copying those over to each of the individual namespaces. I have tried using <code>index.json</code> as a 'fallback' in case the namespace file doesn't define the string. But it doesn't work for me. Contrary to what the <a href="https://docs.microsoft.com/en-us/bot-framework/nodejs/bot-builder-nodejs-localization" rel="nofollow noreferrer">documentation</a> seems to suggest.</p>
  
  <pre><code>/locale
    /en
      /help.json
      /default.json
      /index.json &lt;-- Doesn't work
  /dialogs
    /help.js
    /default.js
  bot.js
  </code></pre>
  
  <p>Say I have the following library in <code>help.js</code>, that :</p>
  
  <pre><code>lib = new builder.Library('help')
  lib.dialog('/', (session) =&gt; {
    session.send('custom_cancel')
  }
  module.exports = lib
  </code></pre>
  
  <p>The library is used in <code>bot.js</code>:</p>
  
  <pre><code>bot.library(require('./dialogs/help'))
  </code></pre>
  
  <p>And <code>index.json</code> has this content:</p>
  
  <pre><code>{
    "custom_cancel": "My custom cancel"
  }
  </code></pre>
  
  <p>Whereas <code>help.json</code> is empty:</p>
  
  <pre><code> {}
  </code></pre>
  
  <p>Because <code>help.json</code> does not have <code>custom_cancel</code>, the bot will actually send <code>custom_cancel</code> as the string.</p>
  
  <p>Again. I can copy paste the strings to both locations and there is no more problem. But that seems like an ugly solution to me.</p>