removed Function interface from img module

modules/gui/pymod/export_plot.cc

modules/gui/src/data_viewer/img2qt.cc

modules/img/alg/src/highest_peak_search_3d.cc

modules/img/alg/src/highest_peak_search_3d.hh

modules/img/alg/src/histogram.cc

modules/img/alg/src/histogram.hh

modules/img/alg/src/stat.cc

modules/img/alg/src/stat.hh

modules/img/alg/src/stat_min_max.cc

modules/img/alg/src/stat_min_max.hh

modules/img/base/pymod/CMakeLists.txt

modules/img/base/pymod/export_data_algorithm.cc

modules/img/base/pymod/export_function.cc

modules/img/base/pymod/export_image_handle.cc

modules/img/base/pymod/export_image_list.cc

modules/img/base/pymod/wrap_img.cc

modules/img/base/src/CMakeLists.txt

modules/img/base/src/algorithm.hh

modules/img/base/src/data.hh

modules/img/base/src/data_algorithm.hh