Cleaning up filenames in root directory of MM

[Kasper Sørensen <i....@gmail.com>]

Hi guys,

I was wondering if we can clean up the (style of) filenames in the root of
MetaModel. I just started working on a CONTRIBUTE.md file and it occurred
to me that we have a big mix of stuff; files without extension (README,
LICENSE etc.), txt files (CHANGES.txt) and now also .md files (which are
great for GitHub integration).

I suggest we choose .md as the preferred format for non-legal files
(retaining LICENSE and NOTICE as is).

And I suggest we remove the .txt file extension (basically rename
CHANGES.txt to CHANGES.md).

Any thoughts, objections?

Kasper