Fix encoding of string that contains "- " (#657)

* fix encoding of string that contains "- "

* fix test case

fix format with empty value (#654)

Fix format indent (#653)

* fix indent of formatted text

* add space to origin buffer for implicit null token

Fix format with alias (#648)

* fix format with alias

fix format with comment (#645)

add node formatter (#644)

fix comment map (#635)

Fix indentation for raw string newlines (#625)

#292

fix flow sequence with map (#620)

Fix tag with flow sequence (#618)

* fix tag with flow sequence

* fix lint error