bitkeeper revision 1.1392 (4270eaf9Zx1D03KOAVKHY8tW-aANmg)

bitkeeper revision 1.1392 (4270eaf9Zx1D03KOAVKHY8tW-aANmg)

Apply Nguyen's patch:

- extend filesystem abstraction by adding file_exist() method. this
method is used to check for existent of a file given its name. now
ext2fs implements this method.
- pygrub opens and parses /boot/grub/menu.lst or /boot/grub/grub.conf,
in that order.
- add /usr/lib/python to system path (see pygrub). without this
change, pygrub cannot find grub python package.
- remove few blank lines

Signed-off-by: Nguyen Anh Quynh <aquynh@gmail.com>
Signed-off-by: Mike Wray <mike.wray@hp.com>