patch 7.4.1486
Problem:    ":loadplugin" is not optimal, some people find it confusing.
Solution:   Only use ":packadd" with an optional "!".
diff --git a/src/testdir/Make_all.mak b/src/testdir/Make_all.mak
index 4c3c616..854f95b 100644
--- a/src/testdir/Make_all.mak
+++ b/src/testdir/Make_all.mak
@@ -178,7 +178,7 @@
 	    test_increment.res \
 	    test_json.res \
 	    test_langmap.res \
-	    test_loadplugin.res \
+	    test_packadd.res \
 	    test_perl.res \
 	    test_quickfix.res \
 	    test_syntax.res \