Revert "docs: Installation on Mac OS X 10.6 Snow Leopard"

This reverts commit 9379917c0c876c9fc760f768938dc45b5a3a4efa.
Revert "Revert "docs: Installation on Mac OS X 10.6 Snow Leopard""

This reverts commit c63b22ce06b2cbd52439672dfd93982f4f489ae5.