refactor: Make formatters functions

Formatters have been classes so far which contained some data (the
tamplate to use for formatting and the annotations and documents to
format) and the actual formatting logic (an execute function).

However, we can inject the annotations to be formatted and the templates
so far are static only, so they can be simple variables (we can think
about how to inject them at another point should it come up, no
bikeshedding now).

This way, we can simply pass around one function per formatter, which
should make the code much lighter, easier to add to and especially less
stateful which means less areas of broken interactions to worry about.

papis_extract/__init__.py

@@ -8,12 +8,7 @@ import papis.strings
 from papis.document import Document
 
 from papis_extract import extractor, exporter
-from papis_extract.formatter import (
-    CountFormatter,
-    CsvFormatter,
-    MarkdownFormatter,
-    Formatter,
-)
+from papis_extract.formatter import Formatter, format_count, format_csv, format_markdown
 
 logger = papis.logging.get_logger(__name__)
 
@@ -82,11 +77,11 @@ def main(
         return
 
     if template == "csv":
-        formatter = CsvFormatter()
+        formatter = format_csv
     elif template == "count":
-        formatter = CountFormatter()
+        formatter = format_count
     else:
-        formatter = MarkdownFormatter()
+        formatter = format_markdown
 
     run(documents, edit=manual, write=write, git=git, formatter=formatter)
 
@@ -98,8 +93,10 @@ def run(
     write: bool = False,
     git: bool = False,
 ) -> None:
-    formatter.annotated_docs = extractor.start(documents)
+    annotated_docs = extractor.start(documents)
     if write:
-        exporter.to_notes(formatter, edit=edit, git=git)
+        exporter.to_notes(
+            formatter=formatter, annotated_docs=annotated_docs, edit=edit, git=git
+        )
     else:
-        exporter.to_stdout(formatter)
+        exporter.to_stdout(formatter=formatter, annotated_docs=annotated_docs)