rebar3/priv/templates/otp_rel.template

{variables, []}.
{template, "app.erl", "apps/{{appid}}/src/{{appid}}_app.erl"}.
{template, "sup.erl", "apps/{{appid}}/src/{{appid}}_sup.erl"}.
{template, "otp_app.app.src", "apps/{{appid}}/src/{{appid}}.app.src"}.
{template, "rebar.config", "rebar.config"}.
{template, "relx.config", "relx.config"}.
{template, "sys.config", "config/sys.config"}.
{template, "vm.args", "config/vm.args"}.
{template, "gitignore", ".gitignore"}.
{template, "LICENSE", "LICENSE"}.
{template, "README.md", "README.md"}.