Add property to exclude instances where variable is null or undefined

{ // same as 1.x
  "name" : "variable_Name",
  "type" : "string", // boolean, number, string
  "filterForUndefined" : false, // default false, filters for undefined variables (ignores filter sub data values if true)
  "filterUndefined": false // default false, removes instances where variable is null/undefined
  "data" : {...}
}