Feature Request: Permission inheritance

Hi Hasura team, really love using your product and would like to give some user feedback. I am not sure if this was brought up before, but I really wish that this was a feature.

### The problem:
- Table A has complex permissions in place based on multiple tables and relationships.
- I need to base the permission level of table B, C, and D on the permissions of table A. Table A has a direct one to many relationship with B, C and D.

Basically if a user can get to table A then he can get to table B, C and D, else nothing is available. Like an operator in the permission dropdown options "B" -> "A" -> "_can_access"