Proposal for minor breaking change to security module: allow an ApplicationUser to be associated with multiple ApplicationTenancy's

[Dan Haywood]

Just wanted to bring this to the attention of anyone using the (non-ASF)
Isis addson' security module:

https://github.com/isisaddons/isis-module-security/issues/47

If you have any objections/concerns, please comment on that issue

Thx
Dan