Taskfile gains local .Taskfile editing refinement

Taskfile runs task files, a bash (or zsh etc.) script that contains functions that can be called via the runner. These files must be called .Taskfile. The runner detects any taskfiles in the current, parent, grandparent etc directory of the directory you’re in.

I’ve refined the edit task that ships with the script so that it opens the .Taskfile in the current directory if it exists, before falling back to editing the runner.