Development repo now at forge.sourceware.org/gcc-a68

[Jose E. Marchesi]

Hello people!

The development repository has just been moved from

  https://forge.sourceware.org/jemarch/a68-gcc

to the gcc organization

  https://forge.sourceware.org/gcc/gcc-a68

Note how the repository has been renamed from a68-gcc to gcc-a68 to
follow the existing convention under gcc/.

I have updated gcc.gnu.org/wiki/Algol68FrontEnd to reflect this change.
Salud!