WDL v1.3.0

This release includes a number of backwards compatible fixes and improvements to the WDL specification.

Some highlights include:

• else if/else clauses for conditionals.
  • This allows you to more concisely and elegantly express conditional clauses.
• Enumeration types (enum) for defining closed sets of named choices.
  • This prevents silent failures from typos by catching invalid values at validation time rather than runtime.
• The split() standard library function.
  • This eliminates the need for shell workarounds when parsing delimited strings.
• Access to task.previous for runtime access to the previous attempt's computed requirements.
  • This enables dynamic resource allocation patterns like doubling memory on retry.
• Relaxed version imports allowing any WDL v1.x document to import v1.x or lower.
  • This enables better package management and dependency handling across the ecosystem.

See the blog post for an overview or the CHANGELOG.md for more details on what's changed.