Update js/locales/bootstrap-datepicker.fr.js

Specify default format for French language.
Updated readme to cover language changes
Now supports full IETF codes & 2 letter codes

The IETF code (eg  "en" for English, "pt-BR" for Brazilian Portuguese) of the language to use for month and day names.  If a full code (eg "de-DE") is supplied the picker will first check for an "de-DE" language and if not found will check for a "de" language.
Update js/locales/bootstrap-datepicker.it.js
Added Travis-CI support
Fix italian localization

First the common date format we are used to is dd/mm/yyyy, then
add proper accents to days name.
fix example syntax highlighting
Remove travis-ci build status from readme, until issues are resolved
Improve calendar weeks logic to follow ISO 8601
Re-add travis-ci build status
Add a small piece of debugging info to travis script