* Remove use of `Kernel#capture` to find RSpec deprecation warnings
because it has has been deprecated.
* Add `require "active_support"` to setup auto-loading.
Closes#252.
Before to namespace headless policy we needed to use following syntax:
authorize :'project/dashboard'
Now we can use array to specify each constant separately so it looks cleaner
authorize [:project, :dashboard]
Enables `policy(:dashboard) # => DashboardPolicy`.
Policies without a matching model can come in handy when a controller
isn't modeled alongside a resource, e.g. a `DashboardsController`.
The policy lookup by symbol also helps with strong parameters,
since I prefer `policy(:post)` or `policy(@post || :post)` over `policy(@post || Post)`.
