SaveKML bounding box issue

[rniemo]

SaveKML incorrectly computes the east/west boundaries from the data set when no area is specified when calling heatmap().

To reproduce, create any dataset with a wide range of longitude points (like -160 to 160) and create the KML file without specifying any area in the heatmap() function. When displaying the set in google maps with a kml overlay, the heatmap should display from west = -160 to east = 160. Instead, the heatmap displays from west = 160 to east = -160, which is a very narrow part of the map.

The KML file does correctly display in google earth as intended. However, to make the KML file also useable in Google Maps, west should be set as minX and east should be set as maxX. Switching these values does not break the display of the KML in Google Earth.