V2.4.1: new release for CSFML v2.4 (new API)

This is a release compatible to the ABI of CSFML v2.4, but it is different to the previous v2.4 release in that the Ada API is as close as possible to the v2.5.x releases. This will allow linking applications which do not depend on v2.5 calls in older systems, like Ubuntu 18.04 LTS.

Original version v2.4 is now deprecated.