Hm, no I didn't, but it sounds like a good idea. For many of the kinds metadata that I can think of (window width/height, etc), it would be useful they were reactive values, since the program would want to respond to changes in them.

If we do this, we'll also have to figure out a good way to get those values into the `shinyServer()`. Keeping them in `input$.shinymetadata_foo` does have the benefit of simplicity since we can just use the existing infrastructure. On the other hand, a separate `inputMeta$foo` would be more cleanly separated but we'd have to figure out a good way to pass the `inputMeta` object to `shinyServer()`.