PDS: parse correctly MISSING_CONSTANT = 16#FF7FFFFB# as a IEEE754 single precision float expressed in hexadecimal; add support for ENCODING_TYPE = ZIP (data file compressed in a ZIP); recognize IMAGE_MAP_PROJECTION as an object included in UNCOMPRESSED_FILE object (#3939)

git-svn-id: https://svn.osgeo.org/gdal/trunk@25983 f0d54148-0727-0410-94bb-9a71ac55c965