title: Unable to generate jar of openwms and deploy
body: <p>I m trying to deploy org.openwms in my system but deployment is getting failed 
  getting error.</p>
  
  <p>'<a href="https://github.com/openwms/org.openwms" rel="nofollow noreferrer">https://github.com/openwms/org.openwms</a>'</p>
  
  <p>getting an error: </p>
  
  <pre><code>mvn clean deploy -Prelease,gpg
  </code></pre>
  
  <p><strong>Update</strong></p>
  
  <pre><code>getting error [INFO] 
  BUILD FAILURE [INFO] 
  ------------------------------------------------------------------------ [INFO]
  Total time: 18.446 s [INFO] 
  Finished at: 2019-07-23T13:06:06+05:30 [INFO] 
  ------------------------------------------------------------------------ [ERROR] 
  Failed to execute goal org.apache.maven.plugins:
  maven-gpg-plugin:1.6:sign (sign-artifacts) on project org.openwms.services: 
  Unable to execute gpg command: Error while executing process. 
  Cannot run program "gpg.exe": 
  CreateProcess error=2, The system cannot find the file specified -&gt;
  </code></pre>