Scans your whitelist for a particular game to see how many on your list own it. Many props to Sighery for helping me with the API business and for creating the code I butchered to make this.
Added group searching functionality, per item #22. This does have a few bugs, mostly related to very large group sizes and/or private users within a group.
Issue #19 Fixed - was a caching issue, but this has been resolved by not using a cache on the Steam store page. Caching only works from the SG site. Every search from the Steam store will result in 100% API calls for all users.
Title changed per #18 so that it more closely matches the functionality (project title is still "SG-WL-Inventory," but user-visible labels are more generalized.