Make 'git help everyday' work

The "Everyday GIT With 20 Commands Or So" is not accessible via the
Git help system. Fix that.

Move everyday.txt to giteveryday.txt
Update giteveryday.txt to fit man page formatting
Add standard man page section titles.
Also adjust anchor text markup for man page format.
Add giteveryday to the manpages make list
Deprecate the old everyday.txt as *.txto in the same manner
as bd4a3d61 (Rename {git- => git}remote-helpers.txt,
2013-01-31), including a link to the new man page.

Add 'everyday' to the help --guides list
Update git(1) and other links to giteveryday.

Signed-off-by: Philip Oakley <philipoakley@iee.org>