Create the short cache.
cacheTimeout is specified in ms.
Purge the entire cache
Delete a State object from the cache, by its uri
Clean up any dangling references to avoid memory leaks.
Return true if a State object with the specified uri exists in the cache
Store a State object.
This function will clone the state object before storing
ShortCache stores items in the cache for a short time.
The reason in this scenarios it's useful to still have a 'very temporary' cache, is because during many operations
get()may be called in rapid succession, and it also allows for enough time for 'embedded items' to pe placed in the cache and extracted again.