Caching of mobilesettings

As part of the "GetExtraProperties" process in the UserRepository as we validate the MobileSettings I noticed that if we are generating them for the first time, we are not writing them back to the database. The only time we actually cache these to the database is when you do a "ChangeStore" through the UI. This means that all of the users we have that only have access to a single store (which is most of them) will never cache this data and will generate it from scratch on every request. This is probably not a HUGE database hit, but it seems like something easy to skip over and ensure that this part of the code works the same whether you have access to only one store or many.

We may want to research as well a process to Refresh the MobileSettings cache on every login (definitely manual, possibly SSOs as well). This would give us some cover around stale cached data. Even though store names and time zones will not be changing, it might be good to refresh occasionally.