[PATCH] Update writing udev rules docs

[PATCH] Update writing udev rules docs

Here's an update for the writing udev rules document.
- Minor corrections/clarifications
- Added info about using NAME{all_partitions}
- Added more info about udevinfo, simplifying the rule-writing process

You can ignore the diff I sent you yesterday - according to the 20040415 bk
snapshot on codemonkey.org, you haven't applied it yet. This patch
incorporates that update, and some other changes I just made.