snipMate: New C snippts

inc - #include "..."
Inc - #include <...>
prk - printk(KERN_WARNING "%s",);

Signed-off-by: Fam Zheng <famz@redhat.com>
vimrc: Usability improvements

- mutt attachment reminder
- key bindinds
- ui tweaks

Signed-off-by: Fam Zheng <famz@redhat.com>