Issue #2188289 by Jaypan, sun, jibran, Berdir: fix up docs for token functions and methods in regards to anonymous users and sessions
Issue #2103043 by JiriK, batigolix, Sree, ifrik: Fix up hook_help for user module
Issue #2174353 by anemes, bryanlburkholder: Fix up docs for system_retrieve_file
Issue #2183461 by siliconmeadow: Fix reference to nonexistent function in taxonomy docs