for Julia 0.6
Easier to explain with examples.
But basically if you put an include inside an __init__,
then it does not have access to names that were added to the calling namespace by using.

But if you put a using at the top of the included file, then all is good.
(But that I feel should be an error).

Works

all in one file: main.jl

module Foo 
    export fooit
    fooit()=println("IT was fooed")
end

module Bar
    using Foo
    __init__() = fooit()

end

using Bar

running that outputs "IT was fooed"

Doesn't work

Running main.jl gives
** InitError: LoadError: mUndefVarError: fooit not defined
while loading .../initstuff.jl **

in initstuff.jl:

fooit()

in main.jl:

module Foo
    export fooit
    fooit()=println("IT was fooed")
end


module Bar
    using Foo
    function __init__()
        include("initstuff.jl")
    end

end

using Bar

Works (but maybe shouldn't?)

I feel like this should be an error, as directly substituting the contents of initstuff.jl into __init__ would be an error.

in initstuff.jl:

using Foo
fooit()

in main.jl:

module Foo
    export fooit
    fooit()=println("IT was fooed")
end


module Bar
    using Foo
    function __init__()
        include("initstuff.jl")
    end

end

using Bar