rebar3 with private hexpm

gistfile1.txt

In order to create a private hexpm follow the steps from: https://hex.pm/docs/self-hosting

Once you get the file server running, it's time to configure your rebar.config like the following:

```
{erl_opts, [debug_info]}.
{deps, [decimal, relsyncd]}.

{shell, [
  % {config, "config/sys.config"},
    {apps, [test]}
]}.

{hex, [
   {repos, [
      #{name => <<"acme">>,
        repo_verify => false,
        repo_url => <<"http://localhost:8000">>,
        repo_public_key => <<"your hexpm public key here">>
       }
   ]}
]}.

```

References: https://github.com/erlang/rebar3/pull/2346