User/record filtering stuffs

[Tim Williams]

I've been giving the new record filtering stuff a spin today and I've
found bits of it non-obvious.  Mainly with having both o.a.b.user.User
and o.a.b.thrift.generated.User and setUser and UserContext.setUser.
It turns out the UserContext gives the behavior I expected
(implementing a BlurFilterServer) but it's not clear why we need the
seemingly duplicitous classes/services around?  From a user's
perspective, btw, the static setter approach feels uncomfortable.  I
know, "uncomfortable" isn't very constructive - I'm hoping to offer
that when my question is answered:)

Thanks,
--tim