Create 2.6 guides

[takezoe]

We are working on creating Scalatra 2.6 guides on the scalatra-2.6 branch. This issue shows progress of that work.

Outlook

• [x] Philosophy

Development

HTTP

• [x] Routes
• [x] Actions
• [x] Reverse Routes
• [x] Requests & Responses
• [x] GZip
• [x] Flash
• [x] Authentication
• [x] CORS

Async

• [x] Akka
• [x] Atmosphere

Views

• [x] Inline HTML
• [x] Scalate
• [x] Twirl

Resources

• [x] Drop this category

Formats

• [x] File Upload
• [x] JSON
• [x] Command (drop)
• [x] Forms #154

Persistence

• [x] Introduction
• [x] MongoDB
• [x] Riak
• [x] Slick
• [x] Squeryl

Internationalization

• [x] i18n (not exist)

Testing

• [x] ScalaTest
• [x] Specs2

API Design & Documentation

• [x] Swagger #153

After Development

Monitoring

• [x] Logging
• [x] Metrics

Deployment

• [x] Configuration
• [x] Servlet container
• [x] Standalone
• [x] Heroku
• [x] CloudBees (drop)
• [x] Google App Engine