title: mysql and mysql2 not working inside Fission runtime
body: <p>I tried to create my own Fission NodeJS runtime image, I tried to install mysql and mysql2 npm packages.
  My docker file is using node:8-alpine base image.</p>
  
  <p>But always when running a function I am getting the following error</p>
  
  <pre><code>user code load error: Error: Cannot find module 'mysql'
  </code></pre>
  
  <p>I tried to install mysql and mysql2 globally inside my DockerFile, but still without any luck</p>
  
  <pre><code>RUN npm install -g mysql
  RUN npm install -g mysql2
  </code></pre>
  
  <p>I am always updating the environment using the next command:</p>
  
  <pre><code>fission env update --name nodejs --image mindbehind.azurecr.io/fission/nodejs-env
  </code></pre>
  
  <p>But even I tried to remove all functions and all environments and re-install from scratch the new environment and my function.
  I already installed other libraries before so I am sure that I could update the Fission NodeJS environment.</p>
  
  <p>I could not understand why is that, anyone has experienced that before and could solve it?</p>