dt_image_flipped_filter(): "filters" is an uint32_t, not an int

This fixes the build with Clang.
Add a space to separate string literal and macro (eg. "%" PRId64)

This fixes the build with Clang.
std::tr1::shared_ptr isn't supported in Clang, only std::shared_ptr is

Also use std::shared_ptr when C++11 standard is enabled.

This fixes the build with Clang.