Make it possible to assign "in training" Status for any angel-class

[blubbel42]

Hello,
It would be great to have a kind of "angel in training" flag for any angel-class. marking a person as working to be a certain kind of angel.

It should result in:
for shift planning: If one specialist-angel is needed, any specialist-angel may sign up, the shift is filled, but any (one) "specialist-angel in training" may still sign up for a training shift.
Or any "specialist-angel in training" may sign sign up, but the shift is not filled, a full-fledged specialist-angel is still needed.

Then again the flag may be revoked any time, making the angel in training a full specialist angel allowed to sign up for shifts alone.

I think this may reduce the number of needed angel-types and maybe make being any kind of specialist angel more accessable, by making it possible to be declared as "in-training" on choosing a any angel class.

also it would reduce the fiddling with moving angels up one class, or signing up angels in Training manually to already filled/ not suitable shifts.

Special things like "needs driving license" or the like should not be affected.

Hope this was clear enough.

Greetings

Blubbel

[MyIgel]

This is similar to #779 -> it adds additional complexity that needs to be accounted for in multiple locations