Create world.arduino object for global properties

A new object - world.arduino - is created to contain all global
properties and functions related to S4A/Arduino
Merge branch 'issue#19'

Merge with issue#19 branch - creation of world.aruino for global properties
Merge remote-tracking branch 'upstream/master'

Upstream merge
Merge branch 'master' of https://github.com/edutec/Snap4Arduino

Merge upstream
Merge remote-tracking branch 'upstream/master'

Sync with upstream
Connect / Disconnect functionality
Multilanguage

Manages localisation of blocks and messages to different languages.  It
uses files such as s4a-lang-es.js for the localisation configuration.
Merge pull request #23 from elaval/master

Connect / Disconnect functionality