Do not use Shade by default and package in another way for a runnable fatjar

[ilopmar]

We shouldn't package the application by default (mvn package) using the Shade plugin, instead we should create only the application jar. The usage of the Shade plugin should be enabled under a flag -Pshade.

This also makes that we need a way to create runnable fatjars. Explore different options like https://www.baeldung.com/executable-jar-with-maven

[shirishpandharikar]

Something similar to One Jar will be so much better. One Jar unfortunately doesn't seem to be maintained anymore but I've tried the Maven plugin and it works.

[alvarosanchez]

Relates to: #123

[alvarosanchez]

Actually duplicates #104