BASE constant setting: moved all to same base folder in 4dev/tests
check all other CONSTANT settings if they are already set and skip (used
only in Language default set)
Add missing phpunit check for array merge recursive
new Langauge\GetLocale::setLocale() for getting new type lang info from
session, etc
L10n class call chnage of parameters:
NEW: locale, domain, path
OLD: locale, path, domain, legacy(bool)
Temporary auto detect for possible path/domain switch if domain value
has slash inside
Rename all local files to names matching locale folder
en_US -> en
Delete lang folders with symlinks as they are no longer used
Update all header files and class Backend\Admin, ACL\Login,
Output\Form\Generate, Template\SmartyExtend with new language order:
call ::setLocale() afer login class
Update missing test translation strings in all po files
Update phpUnit tests to match all new changes
