More consistent variable naming, e.g. $languageCode

* Renamed some variables, e.g. $language if it does not contain a
  Language object.
* Make use of PHP 5.3's short ?: operator.
* Made some stuff private that just does not need to be protected.

Change-Id: I0cb5068d72bb64578ee1e721720e16bae7916b47
Merge "More consistent variable naming, e.g. $languageCode"