DPL: move writers to plugin

This will allow us at some point to remove the dependency on TTree in the framework,
hopefully saving memory and allowing us to more easily customize the writing backend.

Author: ktf

Framework/AnalysisSupport/CMakeLists.txt

@@ -20,6 +20,7 @@ o2_add_library(FrameworkAnalysisSupport
                SOURCES src/Plugin.cxx
                        src/DataInputDirector.cxx
                        src/AODJAlienReaderHelpers.cxx
+                       src/AODWriterHelpers.cxx
                PRIVATE_INCLUDE_DIRECTORIES ${CMAKE_CURRENT_LIST_DIR}/src
                PUBLIC_LINK_LIBRARIES O2::Framework ${EXTRA_TARGETS} ROOT::TreePlayer)