Bug 2152 - Multiple stickies bugs.dwscoalition.org/show_bug.cgi?id=2152

Allowing multiple stickies to be set both in the post forms, via a sticky module and in the Display tab under Manage account.
Allows for different sticky allocations depending upon account type and attempts to handle switching between account types elegantly.
(Bug 2152) Made changes to User.pm following on from code review discussion.
(github.com/dreamwidth/dw-free/pull/276/files#r3386924)