WP-API/WP-API — pull request #697 by PanManAms (2014-12-09 14:18:42+00:00)
Title: enable getting users by slug OR id, not just ID

As it doesn't seem possible to get a user by nicename / slug, and I needed this functionality, this pull req enables that. It only does 2 small changes:
* Enable /users/ID where ID can be non-numeric
* Check if ID is numeric. If numeric, it is treated as ID, otherwise as slug.