Add task title as slug to URL

[JeanMertz]

Task URLs can be shared using:

• https://automaat.test/#/task/11
• https://automaat.test/#/task/12

This works, but if you are sharing with others, and potentially share multiple tasks, it makes it easier to understand what is what by having the task title slug be part of the url:

• https://automaat.test/#/task/11-customer-capabilities
• https://automaat.test/#/task/12-find-customer-uuid

[JeanMertz]

We should probably add a slug column to the database, to guard against breaking links when renaming tasks (#37). Another solution would be to add another table to keep track of historical task names, and support redirecting from old names to new names, as long as no task takes the name historically used by another task.