Instead of the "T: bug", "T: enhancement" and "T: feature" labels, we could use the new "Type" field for github issues.

In this task, we would

• Create the "Enhancement" and "Discussion" types (must be done by an administrator)
• Set the type of all tickets with one of the three labels using batch operations based on filters.
• Adjust github templates to set the type instead of the label.
• Remove the old labels.

Open question: Do we still need to differentiate between a feature and an enhancement request or is the "significant" label sufficient?