DeIMPLEMENT libssl. Expand the IMPLEMENT_* macros since it is far more

DeIMPLEMENT libssl. Expand the IMPLEMENT_* macros since it is far more
readable and one less layer of abstraction. Use C99 initialisers for
clarity, grepability and to protect from future field reordering/removal.

ok miod@ (tedu@ also thought it was a wonderful idea, beck@ also agreed,
but ran away squealing since it reminded him of the VOP layer...)