Added missing signatures for ST_TPI(), ST_TRI() and ST_Roughness

git-svn-id: http://svn.osgeo.org/postgis/trunk@11552 b70326c6-7e19-0410-871a-916f4a2858ee
Added spatial_index column to raster_columns view. Ticket #2361

git-svn-id: http://svn.osgeo.org/postgis/trunk@11553 b70326c6-7e19-0410-871a-916f4a2858ee
Addition of GUC postgis.gdal.datapath to specify GDAL config variable GDAL_DATA. Ticket #1678

git-svn-id: http://svn.osgeo.org/postgis/trunk@11554 b70326c6-7e19-0410-871a-916f4a2858ee
Added spatial_index column description

git-svn-id: http://svn.osgeo.org/postgis/trunk@11555 b70326c6-7e19-0410-871a-916f4a2858ee
Added docs regarding postgis.gdal.datapath GUC and
postgis_gdal_version()

git-svn-id: http://svn.osgeo.org/postgis/trunk@11556 b70326c6-7e19-0410-871a-916f4a2858ee