The presets for external text editors introduced in e16ec95a16 are
stored in Python files. The names of these files are used to generate
the UI name, and are case-sensitive.
They are currently lower case, but should be title case like other
presets. This commit renames the files so they are title case.
Pull Request: https://projects.blender.org/blender/blender/pulls/110642
Add a user preference to set up a custom text editor for editing text
files with the "Edit Source" action in the UI context menu.
- An operator TEXT_OT_jump_to_file_at_point has been added.
- A custom editor can be set in the user preferences.
- A preset has been included for "Visual Studio Code".
- When the editor is not set, use Blender's internal editor.
Ref !108299.
