MADlib trademark transfer has been received and acknowledged by ASF

[Roman Shaposhnik]

Hi!

just in time for our official ASF TLP press release:
    https://s.apache.org/BSrW
I've another exciting update: the trademark transfer
from Pivotal to ASF has been received and acknowledged
by ASF. I'll be updating a few JIRAs based on that once
the JIRA is back up.

The biggest actionable thing out of this is that we can now
remove DISCLAIMER from our release and update the
website to reflect the trademark assignment.

Thanks,
Roman.