Create tags to track/indicate patient status

There's a need to create tags to indicate the following characteristics of an index case, to support case managers:

• Whether the patient has a sexual partner (by use of a single letter)
• Which district the patient comes from (by use of the first 3 characters of an address)

This will entail:

• Creating server-side settings to enable or disable showing of the tags
• Modifying the app to consume the settings, and to display the tags whenever the setting is enabled and the information implied by the settings available.