refactor(users): update user list to follow new design

- Add global styles for preview layout
- Refactor archive to work with new layout style
- Add new layout styles to users screen
- Replace user details slide-pane with static pane
- Replace user table with user list
- Action buttons changes
- Create users profile page
  - Keep quick view/edit on user list screen
  - Add full profile view/edit
- Styling improvements
  - Add SVG icons to user list page
  - Fix avatar size on profile page
  - Change avatar on activity log, and top bar to be rounded
- Users list > table view refactoring
- Remove ability to switch on/off columns in users list
- Remove UserSettings service
- Remove service for handling user settings in local storage
- Users module > merge directives
- Merge all separate directive files into one
- Move sdUserName directive to common directives file

close #147
refactor(datetime): add superdesk.datetime module with reldate

reldate was part of items module, now it will be in core
refactor(auth): create session service for session info

make auth only do auth and store session via session service
chore(travis): run travis test via grunt ci:travis
fix(auth): stop loading indication on error
fix(auth): handle server error responses
test(auth): add logout test
feat(auth): store auth token into session storage
feat(auth): add check for mandatory fields in login modal
feat(profile): implement user profile view
fix(deploy): fix build and add deploy for devel
feat(users): initial users listing
feat(data): introduce resource provider

there is a `resource` provider on top of `$http` which supports
CRUD for registered resources.
chore(npm): update npm devdependecies
feat(data): add resource.getByUrl method
feat(data): support custom headers via resource config
feat(profile) - change user password

Define UI for user password change