New locations on unregistered provider are active by default

- Make withinDateRange work with undefined values
- Filter out unregistered provider locations from billing
Fix save button enabling after saving
reset-password.html: Forgot to update jquery dependency
Secure /users/*

Don't send sensitive data to client, remove unused delete:/users/:id.
Allows users to be queried using username
Rename dangerously shadowed select2OptionToIdNamePair -> select2OptionToIdUsernamePair
Grey out inactive users in select2's

* On search-page when kavi, and selecting classifier
* On subscriber-management-page, when showing and selecting classifiers
Admin can edit classification author

Also, extract meku.js:select2OptionToUser
Sort search-page results by registration date also if classifier selected
Root can edit classification.registrationDate

Can also clear it.