Upgrade to Rails 4.1, use `paranoia` gem.

* Upgrade to rails 4.1
  * Use paranoia gem for compatibility
  * add ext to allow with_deleted option on belongs_to with less code
  * upgrade binstubs
  * use string names in factories to avoid premature autoloading of constants
Add noop migration to force tests load db schema

Rails 4.1 instroduces some intelligence about migrations and schema loading
for databases in test envs. Because we're doing something unorthodox here,
it needs to be told that there is a migration pending for the test database
(i.e. migration 1, which is a noop) before it will attempt to load the schema.
allow filenames in pub with dots
Merge pull request #30 from PRX/fix/filenames_with_dots

allow filenames in pub with dots
Merge pull request #28 from PRX/feat/rails_4_1

Upgrade to Rails 4.1, use `paranoia` gem.