StatObjectResponse contains delete_marker for existing object

[blackyblack]

StatObjectResponse is initialized with delete_marker true as default value. See this line of code:

minio-cpp/src/baseclient.cc

Line 1871 in 49e578d

StatObjectResponse resp(response);

Since headers do not contain x-amz-delete-marker it still is returned as true.

Solution is to initialize delete_marker field with false.