api: report #method if it is unknown
api#folder/setting/get: get get setting from a folder (by #key or #name)
api#folder/setting/get: can use #rokey for looking up
api#folder/setting/get: move selector to #__folder_get_name_and_key
api#__folder_get_single: get specify path with trailign slash (/)

#btsync strictly checks path name, so /foo/bar/ and /foo/bar is different.
So we need to trick it, by removing all trailing slashes before diff-ing