How to Create Reference Folders in Part or Assembly Files?

I was glancing at the standard 1x1x.125 weldment profile SW offers. We don't use weldments - but I'm always up for learning - as I'm doing...

  1. I know how to create folders for features below the origin in the feature tree, but how does one create such a lovely folder above (as shown as REFERENCES and DIMENSIONS)?
  2. What is that L icon in the sketch (Update: I've searched the forums as someone made a comprehensive list but couldn't find it.)?

SW 2017 SP1.

Yeah I know I should know these answers.

Message was edited by: Scott Casale

SolidworksParts And Features