Fix changed shortcuts not being applied till tweak book is restarted

src/calibre/gui2/keyboard.py

@@ -33,7 +33,7 @@ def finalize(shortcuts, custom_keys_map={}):  # {{{
     Resolve conflicts and assign keys to every action in shorcuts, which must
     be a OrderedDict. User specified mappings of unique names to keys (as a
     list of strings) should be passed in in custom_keys_map. Return a mapping
-    of unique names to resolved keys. Also sets the set_to_defaul member
+    of unique names to resolved keys. Also sets the set_to_default member
     correctly for each shortcut.
     '''
     seen, keys_map = {}, {}

src/calibre/gui2/tweak_book/boss.py

@@ -101,6 +101,7 @@ def preferences(self):
         if p.exec_() == p.Accepted:
             for ed in editors.itervalues():
                 ed.apply_settings()
+            self.gui.keyboard.finalize()
 
     def mark_requested(self, name, action):
         self.commit_dirty_opf()