Documentation/dynamic-debug-howto.txt: convert it to ReST markup

- use a quote blocks where needed;
- fix the chapter/section/subsection markups;
- use ``foo`` for monotonic;
- use .. note:: for the line-range note;
- cleanup whitespaces;
- add it to the user's book.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>