Preliminary pdf support

Consolidate comicbook modules
Do not write to temp dir for comics any longer

TODO

@@ -24,7 +24,7 @@ TODO
         ✓ Context menu: Cache, Read, Edit database, delete, Mark read/unread
         ✓ Information dialog widget
         ✓ Allow editing of database data through the UI + for Bookmarks
-        Include (action) icons with the applications
+        ✓ Include (action) icons with the applications
         Set focus to newly added file
     Reading:
         ✓ Drop down for TOC
@@ -54,6 +54,8 @@ TODO
         Search document using QTextCursor?
         Comic view keyboard shortcuts
     Filetypes:
+        ✓ pdf support
+            Parse TOC
         ✓ epub support
             ✓ Homegrown solution please
         ✓ cbz, cbr support
@@ -67,9 +69,9 @@ TODO
         If there are files open and the database is deleted, TypeErrors result
         Cover culling does not occur if some other tab has initial focus
         Slider position change might be acting up too
+        Take metadata from the database when opening the file
 
     Secondary:
-        pdf support
         Annotations
         Graphical themes
         Change focus rectangle dimensions