handle keys deserialization errors, fixes #1592 (#1701)

* handle keys deserialization errors, fixes #1592

* warning on unsuccesfull geth accounts import

ethstore/src/dir/disk.rs

@@ -73,13 +73,14 @@ impl DiskDirectory {
 
 		let files = try!(files);
 
-		let accounts = files.into_iter()
+		files.into_iter()
 			.map(json::KeyFile::load)
 			.zip(paths.into_iter())
-			.filter_map(|(file, path)| file.ok().map(|file| (path.clone(), SafeAccount::from_file(file, path))))
-			.collect();
-
-		Ok(accounts)
+			.map(|(file, path)| match file {
+				Ok(file) => Ok((path, file.into())),
+				Err(err) => Err(Error::InvalidKeyFile(format!("{:?}: {}", path, err))),
+			})
+			.collect()
 	}
 }