todo

Behavioural changes:
✓ Do not delete all records from database where the file system does not even have a folder corresponding to that model 
  (e.g. rake file_system:to_files:layouts only saves layouts to file_system
  subsequently running file_system:to_db should load layouts from fs to db, 
  deleting any layouts from db which have been deleted on file system,
  but leaving all pages and snippets in DB intact!)
✓ make it play with subversion (don't delete .svn folders on each save!)
✓ If a file is deleted from the filesystem, the corresponding item should be deleted from the database
✓ For pages with layout_id = nil (i.e. inheriting layout from parent), leave layout attribute blank (or <inherit> [layout_name] for info).

rake tasks:
✓ file_system:save -> file_system:to_files
  - file_system:to_files -> db:to_fs
✓ file_system:load -> file_system:to_db
  - file_system:to_db -> fs:to_db

Make configurable:
✓ list of FILTERS (ability to add e.g. sass)
  ✓ make list of FILTERS auto-detect filters
- list of CONTENT_TYPES

bugs:
- two layouts with similar names can confuse issues: 
  sitemap -> sitemap.html
  sitemap.xml -> sitemap.xml.html