Brazil numbers - Fix conflits between services and ndc numbers

Hi,

I have a problem with this specs:
```
context "service numbers" do
    it_splits '55100', ['55', '100', ""]
    it_splits '55199', ['55', '199', ""]
end
```
I tried various ways to separate the numbers, but could only reach this solution.

Now that in general this will not be a problem in the use of the gem.

Anyone have any ideas?