Store project-specific settings in the preferences.

This stores project-specific settings, such as filesystem paths, for each
project, and restores those settings when the project is selected again.
Does not touch settings that haven't been set for the newly selected
project.

blender_cloud/__init__.py

@@ -88,9 +88,10 @@ def register():
         settings_sync = reload_mod('settings_sync')
         image_sharing = reload_mod('image_sharing')
         blender = reload_mod('blender')
+        project_specific = reload_mod('project_specific')
     else:
         from . import (blender, texture_browser, async_loop, settings_sync, blendfile, home_project,
-                       image_sharing, attract, flamenco)
+                       image_sharing, attract, flamenco, project_specific)
 
     async_loop.setup_asyncio_executor()
     async_loop.register()
@@ -102,7 +103,7 @@ def register():
     image_sharing.register()
     blender.register()
 
-    blender.handle_project_update()
+    project_specific.handle_project_update()
 
 
 def _monkey_patch_requests():