message: [readme] update changelog to indicate breaking changes
  Note that `IntoEdges` and `IntoEdgesDirected` were present in 0.4.
diff: @@ -29,13 +29,26 @@ Recent Changes
  - 0.5.0
  + - Breaking changes:
  +
  + - The iterative DFS implementation, ``Dfs``, now marks nodes visited when
  + they are pushed onto the stack, not when they're popped off. This may
  + require changes to callers that use ``Dfs::from_parts`` or manipulate
  + its internals.
  + - The ``IntoEdgesDirected`` trait now has a stricter contract for
  + undirected graphs. Custom implementations of this trait may have to be
  + updated. See the `trait documentation`__ for more.
  +
  + - Other changes:
  +
  - Upgrade to Rust 2018 edition
  - Fix clippy warnings and unify code formatting
  - Improved and enhanced documentation
  - Update dependencies including modern quickcheck
  - Numerous bugfixes and refactorings
  - Added ``MatrixGraph`` implementation
  - - Added ``InfoEdges`` and ``InfoEdgesDirected``
  +
  +__ https://docs.rs/petgraph/0.5/petgraph/visit/trait.IntoEdgesDirected.html
  - 0.4.13
  