mrconfig: register stackedit repository.

Signed-off-by: Emmanuel Roullit <emmanuel.roullit@gmail.com>
gitconfig: use 'vi' as standard editor.

Signed-off-by: Emmanuel Roullit <emmanuel.roullit@gmail.com>
spf-13: update spf-13 library.

Signed-off-by: Emmanuel Roullit <emmanuel.roullit@gmail.com>