Add Gleam (#67)

test-projects/erlang_rebar3/src/mylib.app.src

@@ -0,0 +1,16 @@
+{application, mylib, [
+    {description, "An OTP library"},
+    {vsn, "0.1.0"},
+    {registered, []},
+    {mod, nil},
+
+    {applications, [
+        % OTP dependencies
+        kernel,
+        stdlib
+    ]},
+
+    {env,[]},
+
+    {licenses, ["Apache 2.0"]}
+ ]}.

test-projects/erlang_rebar3/src/mylib.erl

@@ -0,0 +1,17 @@
+%%%-------------------------------------------------------------------
+%% @doc mylib public API
+%% @end
+%%%-------------------------------------------------------------------
+
+-module(mylib).
+
+-export([hello/0]).
+-ignore_xref(hello/0).
+
+-spec hello() -> world.
+hello() ->
+    Ret = world,
+    _ = io:format("~p", [Ret]),
+    Ret.
+
+%% internal functions