Remove unused Guest#create_without_name_validation

* Remove unused Guest creation method
* In InviteeBuilder, use `Guest#create` instead of unused method
* Cleanup and refactoring in the course of bug investigation
* Test guest.has_ever_logged_in defaults to false
* Add missing validation for has_many :votes
* Add tests for Guest name validation
* Extract InviteeBuilder#create_yammer_user method
* Remove downcase call now that `normalize_email` hook does it

Minor
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* Fix test descriptions when inaccurate
* Use more verbose validations and one per line for clarity
* Use private method name to describe whitespace filtering test instead of more general 'filters'
* Add clearer context blocks for InviteeBuilder `if` tree
* Use single quotes when not interpolating
* Break lines running over 80 chars
* Sort attr_accessibles in Guest
* Sort validations in same order as in model
@wip Add acceptance test

* Add acceptance test
* Sort guest_steps by use case and test phase (Given/When/Then)
Move setting of has_ever_logged in earlier

* Guest login was failing because name validation wasn't occurring until after save
* Remove bang to `Guest#has_ever_logged_in`, which should always raise an exception
Use instance variables in GuestController methods

* Use instance variables when calling private methods in GuestController
Move event_id session setting to private method
Extract methods

* Extract frequently used Event.find method
* Extract Guest find_or_initialize method
Remove Guest#initialize_with_name_and_email

* Remove Guest#initialize_with_name_and_email
* Remove Guest#set_has_ever_logged_in (replaced with update_attributes)
* Break long lines
* Shorten Guest specs to use FactoryGirl.create instead of save!
* Refactor Guest specs to test Guest.find_or_initialize_by_email (probably unnecessary since this is a core method)
Sort private methods
Give before_filter a more intention-revealing name
Use bang method when finding things in Controllers