KML tree - structure patch for Mapserver.

[davide85]

When using the mapserver default executable to produce a KML rendering, the output is not correctly visualized in google earth due to some missing objects and wrong specifications. This can be easily checked trying to visualize in the same view different poligons that need to overlay. If one poligon GIS data presents "holes/islands" the KML output is wrogly setup by mapserver and cannot be visualized in the google viewer. The patch, for example, changes also the way the mapserver creates the output structure (e.g. the tag innerBoundaryIs has been substituted whith the outerBoundaryIs). This change in structure has been checked with other GIS softwares. Using the same data (polygon), the GDAL (used also by QGIS) produces a KML output setting rightly the outerBoundaryIs while the mapserver without our patch sets the structure with the innerBoundaryIs tag.