Removed conference_date_string_helper, moved date_string to application_controller

Deleted home_helper.rb
Merge pull request #303 from gopesht/modify_date_helper

Removed conference_date_string_helper, moved date_string helper to application_controller
Unused route for Conference#show
add volunteer fields to user
Merge pull request #310 from gopesht/unused_route

Unused route for Conference#show
fix attachment_default migration
Merge pull request #314 from differentreality/attachment_default

fix attachment_default migration
Merge pull request #312 from differentreality/user_fields_volunteers

Add volunteer fields to user
Adds migration to Email Settings for Venue Updates
Venue update notifications done
Added tests for emails views specs for addition of settings