Problem with heredoc's seems to be that the variables don't get replaced inside it -- e.g. 

    <groupId>$GROUP_ID</groupId>
 
should be replaced by (bear in mind that `GROUP_ID=liviutudor`) :

    <groupId>liviutudor</groupId> 

but it doesn't seem to be the case :( 
Is there  a way around this? Otherwise all the files get generated wrong and the compilation won't work :(