search command

[Yoshinori K. Okuji]

I've implement a new command "search" right now. This is similar to "find" in 
GRUB Legacy, but has more features. I renamed it to "search", because it is 
significantly different from "find" in GNU.

Some supposed usage:

# Find a partition whose label is "Boot Partition" and set the result in root.
search --label "Boot Partition" --set
linux /vmlinuz

# Find a partition which has a file "grub2.cfg" and store it in a variable.
search --file /boot/grub/grub2.cfg --set=VAR
configfile ($VAR)/boot/grub/grub2.cfg

Okuji