Indielib() definition has slightly changed to take into account iOS and SDL

[DarthMike]

SDL makes some special initialization before main on mobile platforms (iOS, Android), so client SDL code 'seems' to run in it's normal main() entry point, but it's instead called after initialization.

This is a hack/workaround on SDL 2.0 API, but it's minimally harmful. What implies for our library, is that our users MUST user Indielib() instead of any kind of main() they want to use, because of this initialization.

We need to change tests, tutorials to use different definition of Indielib(). It's a simple change: We had int Indielib() {

...code

}

Now we do: Indielib_Main() {

...code

}

[DarthMike]

We should change tutorials in wiki when releasing 0.6