cleaner product dropdown

Conflicts:
	app/views/spree/admin/products/issues/_form.html.erb
	app/views/spree/admin/products/issues/_issue_fields.html.erb

Conflicts:
	app/views/spree/admin/products/issues/_form.html.erb
	app/views/spree/admin/products/issues/_issue_fields.html.erb
fixes specs using select2 helper

also, inculde capybara ext from spree core