GitLab

- Test checked state registered for beeing displayed as "Interested", but
  it wasn't
- I have zero clue why this test failed now, but not before. Very strange
  in my view.
  https://github.com/panter/aoz-003/blob/042b3884addfe2292b65d815e5217353b826605f/test/system/volunteers_test.rb#L156
  https://github.com/panter/aoz-003/blob/042b3884addfe2292b65d815e5217353b826605f/config/locales/en.yml#L320
  https://github.com/panter/aoz-003/blob/042b3884addfe2292b65d815e5217353b826605f/config/locales/en.yml#L343
- On the way I couldn't help ordering the volunteer model methods
  to be somewhat grouped by type

- using constant array for symbols from Schedules::DAYS
- using t('dates.day_names') in order to get built in translations
- adapting profiles week plan to use same concept

- new client and volunteer action need to build_schedule again
- client and volunteer validate if they have correct amount of schedules
- the way schedules are built has been slightly refactored

- sorry, I need to bypass process for this instance, but only
  this way I'm 100% sure they'll never end up there.

- if the user left the password field blank, in order to keep existing password
  there would have been a validation error. Now the users email or role can be
  updated and the password stays the same.