feature request: custom fields in presets and shifts

[Soubzar]

Checklist

• I checked that this feature has not been requested before
• I checked that this feature is not in the "wontfix / not planned" list
• This feature will benefit the majority of users

Problem Description / Use Case

It would be interesting to be able to add fields in presets and shifts such as the phone number of the person on call.

Proposed Solution

I have tried to add a phone number field to presets and shifts. I have added it to the db schema and all the files that require it. My issue is that I needed to modify a dozen files manually. Is there an easier solution (with migrations for example) in order to add custom fields ? I tried adding the phone number in the db alone but my migration failed. Does anybody have an idea ?