TODOs

[jameshbailie]

Old TODOS (cerca 2023?) moved from README.md:

• Understand the DHS survey design variables (see this Github issue)
• Data validation (see this Github issue)
• Produce a canonical version of the harmonised dataset using this code. Include it in the list of lab assets and here. Advertise this data file to the team (e.g. at the fortnightly lab meeting). (This would ensure everyone in the team is using the same standardised version of the DHS data and the same IWI.)