Add macros support to jsonata field (#194)

* Add macros support to jsonata field

* Update datasource.ts

* Update datasource.ts

Co-authored-by: Marcus Olsson <marcus.olsson@hey.com>

Author: titilambert

src/datasource.ts

@@ -145,7 +145,12 @@ export class JsonDataSource extends DataSourceApi<JsonApiQuery, JsonApiDataSourc
               .forEach((v) => {
                 bindings[v.name] = v.value;
               });
-
+            
+            bindings["__unixEpochFrom"] = range.from.unix().toString()
+            bindings["__unixEpochTo"] = range.to.unix().toString()
+            bindings["__isoFrom"] = range.from.unix().toISOString()
+            bindings["__isoTo"] = range.to.unix().toISOString()
+            
             const result = expression.evaluate(json, bindings);
 
             // Ensure that we always return an array.