Invalid keys

[davejlin]

Keys with characters before a forward slash will not work.

For example, keys consisting of URLs: "http://foursquare.com/image.jpg"
Interestingly, as long as there's no character in front of a forward slash, the key works, e.g. "/image.com" works.

Discovered when debugging why photo urls would not work as SAMCache keys in the Treehouse Objective C video about using SAMCache to cahce Foursquare photos.

Opened a Treehouse Community discussion about this:
https://teamtreehouse.com/community/samcache-does-not-work-with-foursquare-photo-url-as-key