This reverts commit 82a96afa70212da94de758df859e94cccdb2c805.
We ended up not moving to GitHub's wiki after all and built
https://github.com/icculus/ghwikipp to fill the gap...since the wiki is
back at https://wiki.libsdl.org/, put back the original URLs.
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
