oracle-j{dk,re}8 removal proposal

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

We have various (native) openjdk versions in pkgsrc.

We also still have oracle-jre8 and oracle-jdk8, binary packages for
the Linux versions of Java 8 from Oracle. The distfiles are not freely
available, you have to agree to a license to download them.

I propose removing these packages for these reasons:
- old Java version
- Linux binary
- cumbersome license
- openjdk8 available

 Thomas