Move sql data classes into database setup directory

Edit docker file to install sqlite3.

database_setup/create_database.py

@@ -0,0 +1,13 @@
+"""Small script to create the database if it doesn't already exist."""
+
+import sqlite3
+from pathlib import Path
+
+if not Path("database/dakiny.db").exists():
+    with sqlite3.connect("database/dakiny.db") as con:
+        cur = con.cursor()
+
+        with Path("database_setup/database.sql", encoding="utf-8").open() as file:
+            database_script = file.read()
+            cur.executescript(database_script)
+            con.commit()