removing legacy files to make the repo cleaner and clearer

[SamHollings]

• Please check if the Pull Request fulfills these requirements

• The commit message is clear and concise
• Test for the changes have been added and reviewed
• Documentation has been added to all new features and edited code has had documentation reviewed

• What kind of change does this Pull request introduce? (Bug fix, feature, docs update, ...)

• remove older files so there are just the new "approved" files.

• What is the current behaviour? (Link to a current open issue if possible)

• legacy code from the NHS Codon Python library - good and fine, but confusing because it wasn't directly related to current projects, or signed off.

• What is the new behaviour? (is this a feature change?)

• just the content relating to the data quality rules work with Data Architecture.

• Does this Pull Request introduce a breaking change? (What changes might users need to make in their application due to this PR?)

• no current users, but it does remove functionality, so if they relied on those functions they will need to switch to using Codon Python again.