NetBeans 11.1 beta 4 Java EE 8 support

[Vano Beridze]

Hello,

Tested beta 4.
Reopened https://issues.apache.org/jira/browse/NETBEANS-2776
Created https://issues.apache.org/jira/browse/NETBEANS-2848

I suggest to open persistence.xml in Source View until 2848 is fixed.

Vano