Cells 4.0

TODO

• Cell::build as only public with constant, then ::cell_for with constantize.
• ::namespace MyEngine, the same that we have in Reform + Trailblazer
• Allow all files and assets in same directory (selectport).
• Discuss/fix asset path problems: https://github.com/apotonick/cells/issues/266#issuecomment-76947256
• HTML escaping for properties
• XSS attack protection? http://stackoverflow.com/questions/941594/understand-rails-authenticity-token/26895980#26895980

Done

• mounting cell to a route directly (without controller dependency)
• Make sure asset pipeline works
• self-contained (with JS and CSS) has to work, too!!!
• Named route helpers in rspec-cells: https://github.com/apotonick/cells/issues/269
• Support for cells in engines
• test all edge cases in HAML and SLIM (form_for, etc.), too (make sure they're tested in core as well) https://github.com/apotonick/cells/issues/265 https://github.com/apotonick/cells/issues/247

Conceptual

• No ActionController dependency anymore. If needed, it will be injected via options.
• ActionView replacement with tilt. Minimal implementation with minimalistic layout finder.
• Automatic creation of Twins in line with Representable/Roar/Reform.
• Remove Cell::Rails|Rack|Base.