0.4.1

New Features

• #772 Add DirichletMultinomial distribution.
• #773 (experiment) Add collapse handler to exploit conjugacy relations.

Enhancements and Bug Fixes

• #764 Make exception chaining more user-friendly. Thanks, @akihironitta!
• #766 Relax interval constraint.
• #776 Fix bugs in methods log_prob and sample of VonMises distribution.
• #775 Make validation mechanism compatible with omnistaging since JAX 0.2.
• #780 Fix name dimensions of sample sites under contrib.funsor's plate handler.