update year level .filelist

Added new YYYY/index.html files.

Removed var.mk as such special top level files are
added (or not) in various bin tools.

1992/.filelist

@@ -4,7 +4,7 @@
 1992/.filelist
 1992/.gitignore
 1992/guidelines.txt
+1992/index.html
 1992/mkentry.c
 1992/rules.txt
 1992/.year
-var.mk