Add indent / dedent to docs (#1230)

## Checklist

- [ ] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [ ] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [ ] I have not broken the cheatsheet

Author: pokey

docs/user/README.md

@@ -464,6 +464,16 @@ eg:
 
 Swaps the given tokens.
 
+### Indent / dedent
+
+- `"dedent <TARGET>"` decreases the indentation level of `<TARGET>`
+- `"indent <TARGET>"` increases the indentation level of `<TARGET>`
+
+For example:
+
+- `"indent air"`
+- `"dedent funk bat"`
+
 ### Insert empty lines
 
 - `"drink <TARGET>"`: Inserts a new line above the target line, and moves the cursor to the newly created line