Rename docker config file path in README instructions

Dockerfile runs CMD looking for "/config/config.toml" not "/config/satellite.toml"

Set minimum TLS version to TLS 1.2

List scdoc as dependency

Add Docker build support

This adds a Dockerfile and a short instruction on how to use it to run
Satellite. Since the Makefile requires scdoc to be installed (which is
not present in golang:1.15), the Dockerfile runs go build manually
instead.

Do not use hardcoded address on DNSName

Add man pages

When dealing with directories, we should try to search for a index.gmi files on it.

Add installation instructions to the README

Add a Makefile to easily compile and install satellite

Support multiple hosts and regenerate certificates

Update README.md to reflect certificate generation

gofmt

Add certificate generation

Add contribution docs on README.md

Initial satellite commit