Draft: Rename and standardise templates

This is here as a suggestion, not a solution.

Hoping this will lead to discussions about what the templates should look like and contain.

• Renamed templates to make them nicer in template select when creating a new issue from template
• Added consistent emojis across templates
• Reworked task template to use bug template style question headers
• Slimmed down user story template based on most recent examples of user story issues being generated in the DA projects and what sections they include