debian/copyright: Update copyright attributions.

debian/copyright

@@ -21,7 +21,6 @@ Files: .tx/config
        src/load-graph.h
        src/lsof.cpp
        src/lsof.h
-       src/mate-system-monitor.convert
        src/memmaps.cpp
        src/memmaps.h
        src/openfiles.cpp
@@ -30,8 +29,6 @@ Files: .tx/config
        src/prettytable.h
        src/procman_gksu.cpp
        src/procman_gksu.h
-       src/procman_matesu.cpp
-       src/procman_matesu.h
        src/procproperties.cpp
        src/procproperties.h
        src/selection.cpp
@@ -59,7 +56,6 @@ Files: .tx/config
        ChangeLog
        Makefile.am
        NEWS
-       NEWS.GNOME
        README
        TODO
        autogen.sh