aw-weight fragments

[josephholler]

when adding pharmacy staff : population ratios into towns from fragments, the fragments should be area-weighted in code block starting with comment Calculate weighted service to population ratio for each slice of time (weight correspond to distance from the pharmacy still)

This change requires:

• update code to weight by area in second step of floating catchment
• update all figures and tables in the code
• make sure all figures are up-to-date
• update any numbers in the python notebook narrative
• export updated HTML report
• export updated PDF report
• update figures and specific numbers in the manuscript
• update figures and numbers in the presentation
• register report update on OSF

[josephholler]

Fragments are now weighted as of 3ab5aae