add basic notifications collection
Display notifications in the header
Only sync notifications that are relevant to the user
Merge pull request #1 from OurSharey/notifications

Notifications
add chatroom page
templates ready
create messages collection
test
chat list OK
style modify
style  OK
col-xs
Merge branch 'chatroom'
fix unlogin user can see and enter chatroom
Merge branch 'chatroom'
add accessDenied