add fillcode to site-lisp

Signed-off-by: Micky Ching <mickyching@gmail.com>
snippet: add org mode slide header

Signed-off-by: Micky Ching <mickyching@gmail.com>
puborg: using ubuntu-mono for code block

Signed-off-by: Micky Ching <mickyching@gmail.com>
disable untabify while delete tab

Signed-off-by: Micky Ching <mickyching@gmail.com>
add window navigation key

Signed-off-by: Micky Ching <mickyching@gmail.com>