Wiki pages for 4.0 Beta

I have created wiki pages for 4.0 Beta.

4.0/Beta - Wiki [en] OpenMandriva
4.0/Beta/Release Notes - Wiki [en] OpenMandriva
4.0/Beta/Errata - Wiki [en] OpenMandriva

In view and with regard to Beta release, from now on please edit the Beta pages.

As a remind, the 4.0/New page is meant to summarize OMLx 4.0 features instead, and it belongs to entire OMLx 4.0 release cycle.

Developers are welcome to check and review them as needed.