Students get an email when they are promoted from the waitlist

This will happen if an event's size increases, or another
student cancels.
Fix intermittent errors for redirect

Add assertion of header before checking URL redirect

Fixes: https://www.pivotaltracker.com/story/show/49712465
Job details hint string discusses a wider range of jobs
Merge pull request #161 from eanakashima/master

Le'ts have the "what's your job" example string describe more jobs.
Merge pull request #162 from faun/fix_intermittent_failures

Fix intermittent errors for redirect
updated meetup message to SF Ruby
Merge pull request #163 from missherico/master

Change banner to say SFRuby
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