Throw error if non-number is passed to Zotero.DataObjects.getAsync()
Throw error if non-number is passed to Zotero.DataObjects.getAsync()

Previously, if an id was psased as a string and the id existed in the
cache, an error wouldn't be thrown, but if there id wasn't in the cache
(e.g., because it was in an unloaded library) it would. This requires an
integer in all cases.

Note that, among other things, any code that gets ids from object keys
will need to convert them to integers before passing to getAsync().

gracile-fr/zotero,gracile-fr/zotero,gracile-fr/zotero