Removal of AeroGear user

To see the issue fixed on this PR:

- On master branch

1. `cd wildfly`
2. `docker build -t aerogear/wildfly .`
3. `cd unifiedpush-wildfly/`
4. `docker build -t aerogear/unifiedpush-wildfly .`
5. `docker run -it -p 8443:8443 aerogear/unifiedpush-wildfly`

The issue reported by @danbev must happen.