Merge Lightning backend into Mempool backend

backend/src/api/lightning/lightning-api-factory.ts

@@ -0,0 +1,13 @@
+import config from '../../config';
+import { AbstractLightningApi } from './lightning-api-abstract-factory';
+import LndApi from './lnd/lnd-api';
+
+function lightningApiFactory(): AbstractLightningApi {
+  switch (config.LIGHTNING.BACKEND) {
+    case 'lnd':
+    default:
+      return new LndApi();
+  }
+}
+
+export default lightningApiFactory();