Visualise spread of Seshat variables on world map

[edwardchalstrey1]

• [x] Present/absent vars have a legend
  • [x] Differentiate "unknown" from "uncoded"
  • [x] For clarity, when GADM basemap selected, add a white "basemap" label to the legend
  • [x] Can we make the adding of the variable value to each shape somehow more efficient?
• [x] All present/absent vars from sc, wf and rt apps
• [x] Update the dropdown list nesting to match the categorisation of vars as seen on polity pages
• [x] Check through variables for all variable types e.g. present, categorical, hierarchy, continuous
  • [ ] Check again after implementing everything below

Variables

• Present/absent vars
  • [x] Present/absent vars that are dated
    • e.g. see Ottoman Empire I (core/polity/174) "Gunpowder Siege Artillery"
  • [ ] Human sacrifice vars
• Categorical vars:
  • [x] #109
    • [x] Visualise the years for categorical vars
    • [ ] Add the years for categorical vars to the tooltip (this could get messy) - check if worth doing as there looks to be virtually no years recorded in the db for language variables at least (there is one entry in the db where the language year_from and year_to are not null and one linguistic_family and they are the same as the polity years es_spanish_emp_2)
  • [ ] #115
  • [ ] Religion
    • All the categories under "Religion"
    • "Official Religion" and "Elites" Religion under RT -> Religious Landscape
  • [ ] "Supracultural Entity"
  • [ ] "Government Restrictions -> Frequency of Governmental Violence Against Religious Groups"
  • [ ] "Societal Restrictions -> Frequency of Societal Violence Against Religious Groups:"
  • [ ] "Professions" -> Source of Support"
  • [ ] Any others that use FREQUENCY_CHOICES, PREVALENCE_CHOICES or ORDER_CHOICES in RT models
  • [ ] Human sacrifice categorical vars (look at models.py)
• Continuous vars:
  • [ ] Social Scale
• Numerical category vars:
  • [ ] Hierarchical Complexity
• Complicated vars and var groups:
  • [ ] Identity and location
    • Capitals were already implemented, but may be worth thinking of a different way to visualise that makes the uncoded clearer, as well as displaying original/alternative names etc. This can probably all be stuff that is there on the "Polity" dropdown selection
  • [ ] Political and Cultural Relations
    • Succeeding/Preceding entities could be chained?
    • Others here all need to be looked at carefully
  • [ ] "Religious Landscape -> Widespread Religion"