use resolve_globals on top-level exprs whether compiled or not

[JeffBezanson]

Before:

julia> begin
       sin(2)
       global sin = 1
       end
ERROR: cannot assign variable Base.sin from module Main

julia> begin
       cos(2)
       global cos = 1
       while false end
       end
ERROR: UndefVarError: cos not defined

This is because the second one is compiled, causing us to do early resolution of globals that the block might create (via global cos = 1). With this change, both give an UndefVarError.

[JeffBezanson]

Ok, this is probably not quite right. It would break something like

if condition
    using Foo
else
    global myfoo = ...
end