fix warnings (#32)

auction/src/lib.rs

 #![cfg_attr(not(feature = "std"), no_std)]
 
-use paint_support::{
-	decl_error, decl_event, decl_module, decl_storage, dispatch::Result, ensure, Parameter, StorageMap, StorageValue,
-};
+use paint_support::{decl_error, decl_event, decl_module, decl_storage, dispatch::Result, ensure, Parameter};
 use paint_system::{self as system, ensure_signed};
 use rstd::result;
 use sr_primitives::traits::{MaybeSerializeDeserialize, Member, SimpleArithmetic};