Merge branch 'master' of https://github.com/expertiza/expertiza

Conflicts:
	app/models/assignment.rb
	app/views/sign_up_sheet/_available_slots.html.erb
	app/views/sign_up_sheet/_micropayment.html.erb
	app/views/sign_up_sheet/_num_of_choosers.html.erb
Conflicts:
	app/models/assignment.rb
	app/views/sign_up_sheet/_available_slots.html.erb