Revert "Remove gun.app"

This reverts commit a305d9a.

Author: essen

ebin/gun.app

@@ -0,0 +1,10 @@
+{application, 'gun', [
+	{description, "HTTP/1.1, HTTP/2 and Websocket client for Erlang/OTP."},
+	{vsn, "2.2.0"},
+	{modules, ['gun','gun_app','gun_conns_sup','gun_content_handler','gun_cookies','gun_cookies_list','gun_data_h','gun_default_event_h','gun_event','gun_http','gun_http2','gun_http3','gun_pool','gun_pool_events_h','gun_pools_sup','gun_protocols','gun_public_suffix','gun_quicer','gun_raw','gun_socks','gun_sse_h','gun_sup','gun_tcp','gun_tcp_proxy','gun_tls','gun_tls_proxy','gun_tls_proxy_cb','gun_tls_proxy_http2_connect','gun_tunnel','gun_ws','gun_ws_h','gun_ws_protocol']},
+	{registered, [gun_sup]},
+	{applications, [kernel,stdlib,public_key,ssl,cowlib]},
+	{optional_applications, []},
+	{mod, {gun_app, []}},
+	{env, []}
+]}.