patch by erik
r=joel, kiko
a=myk

patch by erik
r=joel
a=justdave

Consolidates the logout code into Bugzilla::Auth::CGI, and provides
simple front-end wrappers in Bugzilla.pm for use in the CGIs we have.
r=bbaetz, joel; a=justdave.

Adds a set of constants to the logout() API which allow specifying "how
much" we should log out -- all sessions, the current session, or all
sessions but the current one.

Fixes callsites to use this new API; cleans and documents things a
bit while we're at it. Part I in the great COOKIE apocalypse.

logout() method that is proxied through Bugzilla.pm's logout(), and fix
callers to use it.  r=justdave, bbaetz, a=justdave

r,a=justdave

r=myk,jake

r=gerv, justdave
a=justdave

Change code to work arround a perl < 5.8 leak when localising the tied
statement attributes. Also, clear the sql statestack compat stuff so that
the handles are really dead by the time we disconnect

r,a=justdave

r, a=justdave

r=gerv, justdave
a=justdave

r=justdave, myk, joel, preed
a=justdave