AggRateLimitsP takes a list of rate limit responses and dedups them to the last one received of each category.

upper bounds takes higher priority.

parseDurationExtended is like time.ParseDuration, but adds "d" unit.

Reorder participants based on the order in activeList.

PublicUIDName is the name given to keybase1.PublicUID.

ReaderSep is the string that separates readers from writers in a TLF name.

TlfHandleExtensionSep is the string that separates the folder participants from an extension suffix in the TLF name.

BadTLFNameError indicates a top-level folder name that has an incorrect format.

NoSuchNameError indicates that the user tried to access a subdirectory entry that doesn't exist.

NoSuchUserError indicates that the given user couldn't be resolved.

TlfNameNotCanonical indicates that a name isn't a canonical, and that another (not necessarily canonical) name should be tried.

UserDeviceCache looks up usernames and device names, memoizing the results.

UserInfoMapper looks up usernames and device names, memoizing the results.

KeybaseContext defines what chat needs from Keybase.