SD-723 user preferences that can be changed
feat(preferences) - create and endpoint to show resource preferences
refactor(users): make users work with citizendesk

make it importable outside of superdesk

SDS-1
Merge pull request #277 from petrjasek/master

refactor(users): make users work with citizendesk
Merge pull request #276 from amagdas/preferences

feat(preferences) - create a way to register per resource preferences and fetch them