MemberTypes 2.2.4 — creating a member type had never worked: the service passed a null
IShortStringHelper, so the alias was stripped to empty and Umbraco refused the save.
The dashboard now adds, renames and deletes types and shows each one's properties.

MemberGroups 2.2.4 — six of the nine API operations had no way in from the dashboard;
create a group and add a member to one are now reachable. CreateGroup no longer reports
success when it failed.