Moving free space to a dedicate folder
Revert "Do not track page instances, only their numbers."

This reverts commit c1816158fcb383b95aa4e432d883bbf56b7b556d.
Moving to a compacted list structure for the free space, instead of the b+tree
- Fixing the way we are handling startup
- Removing flags, we don't use / need them
fixing wrong variable used
All tests are passing again
Midwork