javascript error on external local storage updates

[stumitchell]

Hi I am getting javascript errors when an external element in my page updates the local storage.
As the StorageEvent's key is a string value cljson->clj throws a syntax error.

This patch fixes this.
#7

[alandipert]

I wasn't able to merge your patch for some reason, but I did add the try/catch. It's in 2.0.1.