Creating the formatter file fails silently if parent folder doesn't exist

[fbricon]

• Execute Java: Open Java Formatter Settings
• change path to path/that/doesnt/exist/formatter.xml
• Click Yes to ' path/that/doesnt/exist/formatter.xml ' does not exist. Do you want to create it? pop up
  => .vscode/settings.json is properly updated with new path
  => path/that/doesnt/exist/formatter.xml is not opened because it has not been created
  => No error message anywhere.

So

• parent folder hierarchy should be created automatically if missing, so the formatter file can be created
• an error message should appear in case of an error.