Xahau support

[shortthefomo]

Let's get this working for Xahau have pathing node running and have experience with submitting pathing payments on Xahau.

There is an issue if you don't spec the NetworkID parameter. Something to be aware of.

[tequdev]

The token page uses the onthedex API, but I don't think this is currently supported Xahau.

We need to make the token page unavailable when we are using Xahau.