severity changes post-release

[Luis Villa <louie ximian com>]

Something I've been thinking about for a while... after release, I'd
like to rename 'critical' to 'crasher' and 'trivial' to 'cosmetic' to
make it slightly more clear to first time users (esp. via bug-buddy)
where to place those kinds of bugs. 

Less concretely: I'd also definitely like to make 'blocker' more clear
(since it implies things that just aren't true) but I'm not quite sure
how best to do it. One possible solution is to split it into two
categories:

*security
*build problem

but that loses us some generality [as does 'critical'->'crasher', FWIW,
which is maybe a consideration.] Any thoughts?

Luis