Add variable documentation

[sheep] / wiki

diff --git a/wiki b/wiki
index 06c150fca744ae5052741ca676e09d7081d0eefe..8c039edd1301fc95e5d4e0570ae7a5d1256d176a 160000 (submodule)
--- a/wiki
+++ b/wiki
@@ -1 +1 @@
-Subproject commit 06c150fca744ae5052741ca676e09d7081d0eefe
+Subproject commit 8c039edd1301fc95e5d4e0570ae7a5d1256d176a