refine update algorithm for items Fix4
refine update algorithm for items Fix5
refine update algorithm for items Fix6
refine update algorithm for items Fix7
refine update algorithm for items Fix8
refine update algorithm for items Fix9
refine update algorithm for items Fix10
refine update algorithm for items Fix11
refine update algorithm for items Fix12
user auth front-end
Merge branch 'master' of heroku.com:ctrl-f