Refactor: move story related code from model.js and view.js to story.js

Use window.story instead of separate functions:
- story.parse instead of parseStory
- story.render instead of renderStory
- story.getAllOnPage instead of getStoriesOnPage
Add story.getAllFromHtml, use it in story.getAllOnPage

Make both public.
Fix: add new line at eof to build/chrome/manifest.js
Move all the initial stuff from common.js to base.js

Also wrap it into function base.start, call it from common.js.
Separate fading out original content to base.hideOriginal
Fix: switch to inline (// ...) comments in base.js
Separate generating base html to base.getBaseHtml, slightly refactor it
Merge branch 'develop'