2.3.0

• Add WriteTransaction::set_two_phase_commit()
• Add WriteTransaction::set_quick_repair() which enables a faster repair mechanism at the cost of
  slower transaction commits
• Durability::Paranoid is now deprecated. Use set_two_phase_commit(true) instead
• Fix various bugs when repairing the database after an unclean shutdown. These could result in
  panics, leaked space in the database file, or database corruption