Various game mechanic and client-side improvements.

- HDI is now calculated using mock health, education, and wealth
factors, more similar to the real HDI. It should now be extremely
difficult to reach and/or maintain a 1.000 HDI. GDP and human
development factors have been tweaked due to the change.
- 10 covert cells are able to be created at a time. In the cell creation
window, type a dash and then an integer for the name of the cell.
- The economic health window shows the country's GDP index next to its
GDP per capita.
- When turning off domestic consumption for the Drugs resource, all
other resources that are gov't-controlled are set to export all.
- Update some inaccurate resource management and tax data for various
countries at the beginning.
- Tourism income for a country is only reduced when the country is
directly being attacked or occupied.
- Birth and death rate caps are tweaked.
- Fixed how Eritrea and Somalia unrealistically gain a lot in GDP a few
months in.