fixed the exception when valiation failed

detail: when subject is has characters less than 3, it will raise an exception
Merge branch 'debug_exception_for_terry'

Conflicts:
	fanfan/app/models/payment.rb
disable the circle function now, it is not ready yet
sort the user by asset on balance page
background of activity passed
Merge branch 'master' into fantuan

Conflicts:
	fanfan/app/models/user.rb
added capybara webkit, and create activity successfully