Add a few default scope type delimiters

[AndreasArvidsson]

pour item and bring after item just in search a white space today

Edit (@pokey):

• [ ] "item" (mostly useful in markdown)
• [ ] "section" (useful for markdown)
• [ ] "element" (useful for html / xml)

[pokey]

We should probably add two newlines for "section", and one newline for "item" while we're here. Ideally we'd do #855, but let's get these 3 fixed as it should be quick and dramatically improve ux for markdown