v0.4.2

0.4.2

• Reduced compile times by adding #[inline(never)] to serde trait implementation
  methods that are monomorphized per type (serializer and deserializer).
• Added optional postbag_fast_compile mode that uses buffered visit_seq
  instead of streaming visit_map for Full struct deserialization, further
  reducing compile times at the cost of buffering struct data in memory.
  Enable with RUSTFLAGS="--cfg postbag_fast_compile".