exporter.py: slugify page titles in JSON and file names

It _should_ be impossible for non-slugified page titles to ened up in the
database, but I found a few in my own collection. I can't seem to reproduce
creating pages with these titles so my guess is that they came from an earlier
verison of Silicon before slugification was as strict as it is now.

Author: cu

silicon/exporter.py

@@ -6,6 +6,7 @@
 
 from silicon.page import get_titles, history, read
 from silicon.related import get as get_related
+from silicon.util import slugify_title
 
 
 def export_db(verbose):
@@ -39,7 +40,7 @@ def export_page(title):
         Export a single page as a dictionary.
         """
         page = {}
-        page['title'] = title
+        page['title'] = slugify_title(title)
 
         # get attributes
         page['attributes'] = {}
@@ -66,7 +67,7 @@ def export_page(title):
     # write each page dict to a JSON file
     for title_row in get_titles():
         title = title_row['title']
-        export_file_path = export_dir / f"{title}.json"
+        export_file_path = export_dir / f"{slugify_title(title)}.json"
 
         with export_file_path.open('w', encoding='utf-8') as f:
             json.dump(export_page(title), f, ensure_ascii=False, indent=4)