replace selenium with poltergeist except where it doesn't work
Merge branch 'develop' into 824_question_tag_add_remove

Conflicts:
	spec/features/responses_flow_spec.rb
begin tagging spec
update spec
add tags field to question form with tokeninput
create tags controller with index action
update token input and controller to work
token input options & translations
prepopulate field
customize result list; copy code from options
refactor suggestions method
Process tag string
create new tags when they don't exist
Refactor question form with hidden inputs
Don't remove input if duplicate tag is still in tokenInput
New tags on new question form
Adjustments for admin mode
Show tags nicely on show page
Tags default order
css tweak