v6.0.0

v3.0.0 => v6.0.0 changelog:

• 7152b64
• fc0c737
• 0373829 (breaking change):
  • Drop built-in "memfs"-based implementation. So if "memory fs" is needed it should be passed from outside to store constructor.
  • Enable "fsync" by default for the default / built-in file system (regular node's "fs" module + atomic write + fs-no-eperm-anymore).
• update dependencies