Merge pull request #37 from phuonghuynh/master

I  wanna get the latest code
Merge pull request #38 from phuonghuynh/master

Fix connection error
Merge pull request #39 from phuonghuynh/master

I  wanna get the latest code
Merge pull request #40 from phuonghuynh/master

Fix appending much div when switching new views
update source code for pie chart
Merge branch 'master' of https://github.com/johnsonpham/TechLooper
Return json data