SuperBuild: upgrade GDAL to 2.1.0
SuperBuild: upgrade GDAL to 2.1.0

removed unused find_package(GDAL) in USE_SYSTEM_GDAL loop.
better if guard using cmake return().
handle configure, build, install command for win and unix.
deactivate gdal drivers not built by SuperBuild.
use SUPERBUILD_PATCH_SOURCE macro to avoid copy of change files

orfeotoolbox/OTB,orfeotoolbox/OTB,orfeotoolbox/OTB,orfeotoolbox/OTB,orfeotoolbox/OTB,orfeotoolbox/OTB