Several commonly used template models do not have "template_" in the title

This includes the following models:

• cube.json
• cube_all.json
• cube_bottom_top.json
• cube_column.json
• cube_column_horizontal.json
• cube_directional.json
• cube_mirrored.json
• cube_mirrored_all.json

This means that alphabetical sorting results in these being separated from other template models, which is less than desirable, and does not immediately indicate that they are templates in the first place, which can cause confusion (e.g. there does not exist a block called minecraft:cube).