Enable users to specify custom titles based on certain fields

What used to be unique was literally relying on `T21:` in the title to find an issue in the ALM. Now with custom titles we can rely on some user-defined string plus `T21`. The task title cannot be relied upon since it can change.

Do you have a better name than `unique`? I wanted to introduce the idea that issues have their own identity and we should be able to look issues up with their identity (more than `T21:`). Right now we rely solely on an issue's title to store the identity.