Rails 4 upgrade! Tests are running but not passing. Changes:
* update a lot of gems
* update application.rb for rails 4
* added config.eager_load to the environment files
* updated conditions hashes on has_many relations
* took out modernizr (maybe we don't need it?)
Run rails 4 migration
Clean up Guardfile and .rspec
Remove faulty sass include directive
Remove whiny_nils
Get rid of rails 4 deprecation warnings:
* .scoped has become .all
* implicit table joins need .references
* scopes need ugly lambdas
* get rid of whiny nils. I hated them.
* secret_token is now secret_key_base
Fix specs for EventsController

* Make stuff attr_accessible on Event
Make all location attributes on the form accessible
Fix rsvps_controller specs by fixing accessible attributes on rsvp and rsvp_session.
Fix migration madness
WIP - Draw the rest of the owl
Make Rsvp#operating_system_id and #class_level attr_accessible
Fix SeedEvent spec

* Make Rsvp#user/#role/#event/#operating_system attr_accessible
* Remove ActiveRecord::SchemaMigrations from the rows counted in seeds
Make reminded_at attr_accessible
Bump devise rails4
Schema diff noise
For devise, filter strong parameters
Make Event#student_rsvp_limit attr_accessible