d strings are the bane of my existance

[rikki cattermole]

The string is not the problem.

```d
string ip_address = "192.168.1.1";
auto x = new InternetAddress(ip_address, 8008);
```

That works.

A string in D is an alias for immutable(char)[]. This is defined in 
druntime (object.d).

Immutable does cast to const implicitly, so a string argument to the 
constructor works fine as it has the same meaning.

The port however, that needs to be a ubyte/ushort to pass in and not be 
a string like you had it.