HttpManager => If data are empty, do not modify content-type

NodeApp/src/managers/HttpManager.ts

@@ -22,7 +22,9 @@ class HttpManager {
             }
 
             if ( config.url && (config.url.indexOf(Config.apiURL) !== -1) ) {
+                if ( config.data && Object.keys(config.data).length > 0 ) {
                     config.headers['Content-Type'] = 'multipart/form-data';
+                }
 
                 if ( SessionManager.isLogged ) {
                     config.headers.Authorization = 'Bearer ' + SessionManager.token;