fixed BaseClient's type map, so it is really unique for each client (fixes #252)
test cases for 'change' event in BaseClient, fixed inconsistency with module events
setting a node pending should also set the parent pending, unless it has force flags
getListing: flag directory nodes 'pending', when no force is set; getFile: check parent 'pending' flag as well when deciding whether to fetch from cache or remote (refs #248)