[julia-users] export @enum type should also export its values

[Sisyphuss]

Let's see this example:
```
module tmp

export FRUIT, f, apple

@enum FRUIT apple=1 orange=2 kiwi=3

f(x::FRUIT) = "I'm a FRUIT with value: $(Int(x))"

end
```

f(apple) works fine
f(orange) doesn't work
f(FRUIT.apple) doesn't work either. 

An enumerate type is of no use, if can't use its values. 
Therefore, export an enumerate type should implicitly export its values.