0.15.1: Scottish Fold

This is a special Scottish Fold release. I had trouble finding a good release name, so I googled for cat breeds...

Look at this fella:

Anyway, small release:

Breaking

• None.

Enhancements

• Improve performance of Yaml parsing.
  JP Simard
  #289

Bug Fixes

• CXComment.commandName() was returning nil on custom code comments
  since Xcode 8.1. This caused a force unwrap when generating
  documentation. Inline command comment is now used as a
  fallback to catch this edge case.
  Jérémie Girault