document __files

Signed-off-by: Nico Schottelius <nico@bento.schottelius.org>

docs/man/cdist-reference.text.sh

@@ -75,6 +75,10 @@ confdir::
     By default it consists of everything in \$HOME/.cdist and cdist/conf/.
     For more details see cdist(1)
 
+confdir/files/::
+    Cdist does not care about this directory besides providing access to it.
+    It is thought to be a general file storage area.
+
 confdir/manifest/init::
     This is the central entry point.
     It is an executable (+x bit set) shell script that can use
@@ -196,6 +200,10 @@ The following environment variables are exported by cdist:
 __explorer::
     Directory that contains all global explorers.
     Available for: initial manifest, explorer, type explorer, shell
+__files::
+    Directory that contains content from the "files" subdirectories
+    from the configuration directories.
+    Available for: initial manifest, type manifest, type gencode, shell
 __manifest::
     Directory that contains the initial manifest.
     Available for: initial manifest, type manifest, shell