add cli gramar

TQL

@@ -119,3 +119,13 @@ disk1_path: disk 1 path (eg: /dev/vg/sex)
 disk1_size: disk 1 size (eg: 1024)
 disk1_pool: storage pool back reference (eg: vg) [vmonly]
 disk1_voln: storage pool volume back reference (eg: ) [vmonly]
+
+== grammar ==
+input: prop EOL
+prop: "(" prop ")" | stat
+stat: prop sep prop | prop mod word | close
+close: word [ op word ] | ¤
+sep: "&" | "|"
+mod: "^" | "%" | "$"
+op: "=" | "!=" |  ":" | "!:" | "~" | "!~" | ">" | ">=" | "<" | "<="
+¤: