Update README.md

Fixed the license for Vaadin Charts
Forgot to specify JDK version. Added it to pom.
Update DataProvider.java

Removed my own Rotten Tomatoes API key from the source.
Fixed unwanted variable division

Sass arithmetics are now supported in Vaadin 7.1, so the font declaration was causing an exception in the compilation.
Updated to Vaadin 7.1.0

Removed unnecessary dependencies to CSSInject and Calendar, as both are
now part of the core framework (although style injections work in a
slightly different manner).

Fixed a line of Sass that was causing compiler errors.
Updated readme

Removed mentions to add-ons that are no longer used.
Fixed a CSS class name error

Some movie titles contain the & character, which is not a valid CSS
class name character.
Removed the Rotten Tomatoes API key (again).

Please use your own API key :)
One more fix to the CSS class name errors
Sync with https://github.com/vaadin/dashboard-demo.git

1. syncwithupstream.sh to sync with vaadin/dashboard-demo.git
2. Code merged with vaadin/dashboard-demo.git