add lang zh-TW
add lang zh-TW
updated new entries and corrected the existing ones for PL lang
updated new entries and corrected the existing ones for PL lang
Merge pull request #1 from Gadoma/patch-2

updated new entries and corrected the existing ones for PL lang
Merge pull request #447 from Gadoma/patch-1

updated new entries and corrected the existing ones for PL lang files
Merge pull request #441 from lokielse/master

Add i18n zh-TW language pack.
Added class_exists check to AdministratorServiceProvider boot to prevent redefinition of AdministratorBaseController alias. This prevent errors in Laravel 4.1 phpunit tests.