- it doesn't reload the page
- it shows model save errors as list
- it renders json response from the xhr action to template passed to api_button
  - using lodash tmplate

use advanced instead of duration, as it is more timezone safe

fix and make tests with Time more explicit and timezone safe

fix format helper test

fix format helper test

remove tz_parse helper

- use the methods included to BillingExpense from concern
- try to make string output format more readable

- and also display "1. Semester 2018 - 2. Semester 2019"

- the profile_link helper was delivering a path, but not a link
- renamed profile_link to profile_url_path (not profile_path to not conflict with path helpers)
- created new method profile_link, that creates a real html link of the user with its full name
  - it also checks for current_user policy credentials, edit? or show? and if none of them, it shows
    the users full_name and email as pure text

change action name helper to controller and action name helper, plus use them in views, to shorten conditionals