Implement an option to apply migrations along with executing sqlmigrate

[kekekekule]

The flow is exactly:

• lint migration X
• apply migration X
• lint migration X'
• apply migration X'
  etc.

The main reason is that:

1. Some migrations require the previous ones to be applied (e.g. changing unique constraints)
2. We can lint not only the migrations' SQL, but also check whether migrations can be applied from scratch

I suggest a new flag like --migrate-from-scratch that could make the linter behave like this. The only limitation is this the option can clash with some other (app_label, migration_name, include-name, etc)

[kekekekule]

I wanna implement this maybe in a month, when I'll have enough of free time