Allow execution of portal's and manager's CGI in shell
It may be useful to run portal's and manager's CGI in shell, for debug or advanced feature. Till now, the only thing which make it impossible is a call to $ENV{SCRIPT_FILENAME} to determine html templates directory. Besides, LL::NG::Portal::Simple->getApacheHtdocsPath should better be in LL::NG::Common::CGI, so they could be used by manager's CGI.