We're going to issue a pull request to get into the master podspec repo. In the meantime, just aim your Podfile at our repo!
pod 'NSLayoutConstraint+HAWHelpers', :git => 'https://github.com/howaboutwe/NSLayoutConstraint-HAWHelpers.git'
Written by Brad Heintz and James Paolantonio for HowAboutWe/This Life, Inc. Copyright © 2013 This Life, Inc.
Apache License 2.0. Go ahead and fork the repo, and send along pull requests if you feel you have changes to share.
The method signatures should tell you pretty much everything you need to know about how to use them. For information on Auto Layout generally, see Apple's docs on the topic.
Note that the selection of methods is deliberately not comprehensive - it just gives you a fast way to do the basics.