limited minimum and maximum zoom on camera
changed point scaling so that cities get smaller when zooming in
changed selection cursor to hollow circle
changed capital cities to orange squares
included data/earth/ directory so that files are loaded from there when they're not available in the mod folder
when cities are hidden, hovering over travel nodes will display the travel node location (broken for now)
when cities and travel nodes are hidden, hovering over ai markers will display their details
made the information boxes more opaque
changed border-calculating code so that it works with higher resolutions
Mouseover to find nearest city and display information.
Camera movement via arrow keys and scroll wheel.
Status bar displaying mouse location in world and window coordinates.