SWC-440: support email search, as well as last name prefix lookup
remove email, will not work unless we move this logic to the manager level or expose email from the manager level
SWC-440: from code review - clear private fields at the service level.  add unobfuscated email address as prefix key for item, enable finding a user by email address
Merge pull request #391 from jay-hodgson/SWC-440

Swc 440: add ability to search by last name