Changes from 3.0.1 to 3.0.2

• Fix for windows when using ctx API from multiple threads. Closes #763.
  Thanks to Christoph Gohlke (@cgohlke).

• Harden metalayer APIs against invalid lengths and unsafe memory usage.
  PR #758. Thanks to @metsw24-max.

• Fix DELTA pipelines after byte-transforming filters (e.g. shuffle).