Prettier does not use `.prettierignore` unless the current directory is the root where the `.prettierignore` file resides.
* Update Prettier tests
* Look for prettierignore to determine project root
* Set `--parser` option in Prettier's fixer
* Add expected `--parser` option to tests
* Disable Prettier `--parser` detection if file extension exists
* Manually default Prettier `--parser` to "babylon"
* Add `--parser` test for TypeScript
* Add tests for Prettier `--parser`
* Add JSON5 to the suggested fixer for Prettier
* Add prettier fixer support for typescript
* Add prettier fixer support for css and scss
* Add prettier fixer support for json
* Use getbufvar() to get &filetype
* Add support for prettier configuration file.
As of version 1.6.0, prettier allows passing a `--config` argument with
a path to a configuration file.
* Add test prettier configuration file.
* Add option to use local prettier configuration.
* Add description for new prettier option.
* Also check if the config is present before using it.
