- overwrite myth/auth config with castopod app needs
- create custom views for users authentication
- add admin area bootstrapped by admin controller
- shift podcast and episodes crud to admin area
- reorganize view layouts
- update docs for database migration
- add myth-auth to DEPENDENCIES.md

closes #11

- refactor model / entity and controller logic for DRY code
- update episodes and podcasts
migrations
- define callbacks for podcast and episode models for enclosure update and cache
clearing

- refactor episode, podcast and category entities to add dynamic properties
- refactor Routes when adding feed route
- update migration files to better fit itunes' and rss' specs
- update podcast and episode forms
- add SimpleRSSElement class to Libraries
- add rss_helper
- update home controller to redirect if system has only one podcast