Improve debugging with f_eval_catch() introduced by SVN r257784 and also
fix a bug where "pkg update" was not getting the value of PACKAGESITE.
NB: PACKAGESITE needs to be explicitly exported in support of children.

MFC after:	3 days
Always shutdown the media when we're exiting the packages module (prevents
errors on re-entry for physical media). Also, while we're here, stop
ejecting the CDROM when we're done with it (but leave the functions for
later use so that we could perhaps -- from the installer standpoint -- use
it to eject the media after an install).

MFC after:	3 days
Fix package installation from physical media such as DVD.

Discussed with:	re (gjb)
MFC after:	3 days
Do not assume a value for #address-cells when parsing the OF translations
map. This allows the kernel to get farther with OpenBIOS on 64-bit CPUs.
Refactor draw-beastie function.

Discussed on:	-hackers
Add a try-include word (which acts the same as "include") and use it to
conditionally include (but ignore failures) /boot/loader.rc.local and
/boot/menu.rc.local -- to make customizing the menu easier.

Reviewed by:	alfred
Discussed on:	-hackers