Improvements

I've made fixes in three areas:
1) Python
- be more Pythonic (optimize imports, be PEP 8 conforming)
- fixes to small coding errors
2) CSS 
- optimized & fixed several incorrect (duplicated, miss typed name, etc) CSS properties in dashboard.css and style.css
3) JavaScript
Fixes to dashboard.js: 
- proper formatting
- terminate functions statements
- cache jQuery selectors in variables for reuse