add support for graphite functions: maximumAbove maximumBelow minimumAbove

src/app/services/graphite/gfunc.js

@@ -294,6 +294,27 @@ function (_) {
     defaultParams: [25]
   });
 
+  addFuncDef({
+    name: 'maximumAbove',
+    category: categories.Filter,
+    params: [ { name: "value", type: "int" } ],
+    defaultParams: [0]
+  });
+
+  addFuncDef({
+    name: 'maximumBelow',
+    category: categories.Filter,
+    params: [ { name: "value", type: "int" } ],
+    defaultParams: [0]
+  });
+
+  addFuncDef({
+    name: 'minimumAbove',
+    category: categories.Filter,
+    params: [ { name: "value", type: "int" } ],
+    defaultParams: [0]
+  });
+
   addFuncDef({
     name: "exclude",
     category: categories.Filter,