closes #168
-data from: https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/YUS575
-downloads data spreadsheet and creates csv containing country code, political leader name, latitude coordinate of leader's bitrhplace, longitude coordinate of leader's birthplace
-users can select year and incoming/outgoing leader status
Description
closes #168 -data from: https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/YUS575 -downloads data spreadsheet and creates csv containing country code, political leader name, latitude coordinate of leader's bitrhplace, longitude coordinate of leader's birthplace -users can select year and incoming/outgoing leader status