Content revision status update

[Dmitri Popov]

Hello,

I've finished revising the about.md and features.md pages. I
integrated the content of the overview.md into about.md, as there is
no reason to keep the content split in tiny chunks. Anyway, take a
look and let me know what you think.

Also, perhaps it's better to collaborate on the website via email,
instead of clogging this list. Feel free to contact me at
dmpop at linux.com, so I have your email addresses.

Best,
Dmitri