Add separate package with file formatters.

printer-linter/src/printerlinter/formatters/formatter.py

@@ -0,0 +1,16 @@
+from abc import ABC, abstractmethod
+from pathlib import Path
+
+
+class FileFormatter(ABC):
+    def __init__(self, settings: dict) -> None:
+        """ Yields Diagnostics for file, these are issues with the file such as bad text format or too large file size.
+
+        @param file: A file to generate diagnostics for
+        @param settings: A list of settings containing rules for creating diagnostics
+        """
+        self._settings = settings
+
+    @abstractmethod
+    def format(self, file: Path) -> None:
+        pass