Deploying on Google App Engine

[dataatsky]

Hello,

I am trying to deploy firing-range on GAE however I'm running into issues.
First, trying to deploy as "gcloud deploy app" I get this error:

Error: Server Error
The server encountered an error and could not complete your request.
Please try again in 30 seconds.

Second, trying to deploy as " mvn deploy: appengine" runs into many errors such as there isn't a pom file . Therefore I created the pom file but still got errors such as:

[ERROR] Could not find goal '' in plugin org.apache.maven.plugins:maven-deploy-plugin:2.7 among available goals deploy-file, help, deploy -> [Help 1]

Every time I sort out an error another comes out, which makes me wonder if I am following the correct way.
Can you provide some steps on how to deploy this app on GAE?

Thank you