Supported HEAD method

For example,
my $attr_value = "http://localhost:8080/firstapp/login.html";
print "$attr_value ", LWP::Simple::head($attr_value) ? "OK" :
"!!!***BAD***!!!", "\n";
Should return
# by deafult, HTTP/1.1 200 OK
Implemented Security module

Implemented Security module. It is a Form based authentication.