ENH: Superbuild - Removed unused log4cpp.cmake script

log4qt is now used.

CMakeExternals/log4cpp.cmake

@@ -1,20 +0,0 @@
-#
-# log4cpp
-#
-SET(log4cpp_DEPENDS)
-ctkMacroShouldAddExternalProject(log4cpp_LIBRARIES add_project)
-IF(${add_project})
-  IF(NOT DEFINED log4cpp_DIR)
-    SET(proj log4cpp)
-#     MESSAGE(STATUS "Adding project:${proj}")
-    SET(log4cpp_DEPENDS ${proj})
-    ExternalProject_Add(${proj}
-        DOWNLOAD_COMMAND ""
-        CMAKE_GENERATOR ${gen}
-        SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/Utilities/${proj}
-        CMAKE_ARGS
-          ${ep_common_args}
-        )
-    SET(log4cpp_DIR ${ep_install_dir})
-  ENDIF()
-ENDIF()