Extract {Yes, No, Don't Know} dimensions to a Shared Dimension

[jazzido]

• [ ] less_than_8_blocks_public_transport
• [ ] less_than_20_blocks_educational_center
• [ ] less_than_20_blocks_health_center
• [ ] less_than_20_blocks_market
• [ ] less_than_20_blocks_atm
• [ ] less_than_20_blocks_sports_center
• [ ] less_than_20_blocks_green_areas
• [ ] less_than_20_blocks_community_equipment
• [ ] less_than_20_blocks_pharmacy