Allow for using port 80 on Basics Station

[gbird3]

• [x] I have searched the issues of this repository and believe that this is not a duplicate.

Summary

I should be able to use port 80 for BasicsStation.

What is the use-case?

Using a common port like port 80 allows for easier setup and limits the amount of firewall changes needed.

Implementation description

Currently you can't use port 80 because the request.Host drops the port if it is port 80. It is as simple as checking if the host has a port and if not, add port 80.

Can you implement this by yourself and make a pull request?

Yes. I have code I am testing that implements this.

[brocaar]

I'm closing this, please see my comment on: https://github.com/brocaar/chirpstack-gateway-bridge/pull/189.