feat(auth,policy): add AWS SigV4 authentication and S3 bucket policy support

ts/index.ts

@@ -58,6 +58,7 @@ export interface IServerConfig {
   port?: number;
   address?: string;
   silent?: boolean;
+  region?: string;
 }
 
 /**
@@ -89,6 +90,7 @@ const DEFAULT_CONFIG: ISmarts3Config = {
     port: 3000,
     address: '0.0.0.0',
     silent: false,
+    region: 'us-east-1',
   },
   storage: {
     directory: paths.bucketsDir,