Change format for indexed column and ordering term
Change format for indexed column and ordering term

Indexed columns (e.g., the column list in the `ON` part of a
`CREATE INDEX` statement) and ordering expressions (e.g., the
`ORDER BY` part of a `SELECT` statement) now have the
following format:

- When they are proceeded by an ordering term (e.g., `ASC`, `DESC`) and/or `COLLATE`, such as `ORDER BY nick ASC`
- But, when it is only an expression or column name without any ordering term or `COLLATE` then it will only be the expression itself, and the implicit `"direction": "asc"` will not be added to the AST, such as `ORDER BY nick`

Refs #3

codeschool/sqlite-parser,codeschool/sqlite-parser,codeschool/sqlite-parser