yui/yui3 — pull request #1804 by andrewnicols (2014-05-05 10:04:17+00:00)
Title: Clarify documentation and logic for Attribute.modifyAttr

Whilst explaining to a colleague why we were using modifyAttr for something, I discovered that the documentation is unclear about using it to add new attributes.

I also took the opportunity to simplify the codebase slightly.