Remove grub messaging on the happy-path

[Joshua Warner]

Hi,

I'm looking to remove grub messaging from the boot cycle, unless something
goes wrong.  I like my boot screens to have as little mode-change flashing
and text flying past as possible, from an aesthetic perspective.  Plus, they
might scare users who aren't familiar with GRUB.

Removing the menu is as simple as `set timeout=0` in the config, but the
"Welcome to GRUB" and "Booting `<item>'" messages are trickier - they seem
to be hard-coded.

I have few questions:
* What's the purpose of these messages?
* Why are these hard-coded?
* Might patches be accepted to remove them, or at least make them
configurable?

For reference, I'm talking about grub-core/kern/main.c:274 and
grub-core/normal/menu.c:814.

Thanks,
Joshua