fixed cleanObject output for @value = 0 (#163)

* fixed cleanObject output for @value = 0

Signed-off-by: NeelParihar <[email protected]>

Author: Neelterminusdb

lib/query/woqlCore.js

@@ -344,7 +344,7 @@ WOQLQuery.prototype.cleanObject = function (o, t) {
     t = t || 'xsd:boolean';
     obj.data = this.jlt(o, t);
   } else if (typeof o === 'object' && o) {
-    if (o['@value']) obj.data = o;
+    if (typeof o['@value'] !== 'undefined') obj.data = o;
     else return o;
   // eslint-disable-next-line no-dupe-else-if
   } else if (typeof o === 'boolean') {