- update to 1.4.2:
- Documentation: Basic usage examples in `README.md`. (#141)

Changed:
- More detailed error message in case of Graphviz errors. (#239)
- More detailed warning message in case of failure to import the DOT
parser module. (#241)

Deprecated:
- A future pydot 2.0.0 will drop support for Python 2, 3.4 and
possibly other Python versions that are end-of-life at that time.
Pydot does not emit any deprecation warnings about this. Further
pydot 1.x.x releases are currently not foreseen, but if there are
any, should still support the mentioned Python versions. (#229)

Fixed:
- On Python 2, non-equality comparison (`!=`) between two separate, but
equal `Edge` instances will now correctly return `False`, as it
already did on Python 3. (#248)
- Prevent `TypeError` in handling of DOT parser error. (#176)
- Prevent `TypeError` in `graph_from_adjacency_matrix()` and
`graph_from_incidence_matrix()`. (#98)
- Prevent `TypeError` when creating an edge with a `Subgraph` or
`Cluster` object (as opposed to name string) as an edge point. (#89)
- Windows only: Fixed most failures to find Graphviz when a conda or
Anaconda installation exists, but Graphviz was installed manually or
through pip (`.bat`/`.exe` suffix problem). (#205)
- Windows only: Fixed failure to run Graphviz related to side-by-side
assembly (SxS) by now propagating the `SYSTEMROOT` environment
variable. (#208)