Documentation/ManagementStyle: convert it to ReST markup

- Convert document name to ReST;
- Convert footnotes;
- Convert sections to ReST format;
- Don't use _foo_, as Sphinx doesn't support underline. Instead,
  use bold;
- While here, remove whitespaces at the end of lines.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>