add built-in Model 'Department'

Signed-off-by: Henry Chen <hchen@vmware.com>
Merge pull request #1 from Henry-CF/master

Add model 'Department'.
add model spec skeleton
merge latest code from vmw-tmpst
Merge pull request #2 from easeway/user-login

add model spec skeleton
add libnotify for linux
Merge pull request #4 from whywhy36/notification

add libnotify for linux
Add system design document
Merge pull request #5 from xiebing/master

Add system design document
use devise for user login logic
Merge branch 'master' of github.com:vmw-tmpst/heroapp-LetsHire into user-login
add missing libnotify gem
Merge pull request #6 from easeway/user-login

User login basic feature complete [46355839]