build_draft_stats, total_original_post_notes_by_qtr_and_year, other minor improvements

build_draft_stats_model.py

@@ -0,0 +1,12 @@
+from dataclasses import dataclass
+from stats_model import StatsModel
+
+
+@dataclass(kw_only=True)
+class BuildDraftStatsModel(StatsModel):
+    """Stats model built around calculating stats from your currently drafted posts"""
+    operation: str = 'build_draft_stats'
+
+    def __post_init__(self):
+        super().__post_init__()
+        self.most_popular_tags = self.determine_most_popular_tags('post_count')