[docker] update dockerfile, add configuration file (#1788)

Signed-off-by: R4SAS <r4sas@i2pmail.org>

contrib/docker/i2pd-docker.conf

@@ -0,0 +1,52 @@
+## Preconfigured i2pd configuration file for a Docker container
+## See https://i2pd.readthedocs.io/en/latest/user-guide/configuration/
+## for more options you can use in this file.
+
+## Note that for exposing ports outside of container you need to bind all services to 0.0.0.0
+
+log = file
+loglevel = none
+
+ipv4 = true
+ipv6 = false
+
+# bandwidth = L
+# notransit = false
+# floodfill = false
+
+[ntcp2]
+enabled = true
+published = true
+
+[ssu2]
+enabled = true
+published = true
+
+[http]
+enabled = true
+address = 0.0.0.0
+port = 7070
+
+[httpproxy]
+enabled = true
+address = 0.0.0.0
+port = 4444
+
+[socksproxy]
+enabled = true
+address = 0.0.0.0
+port = 4447
+
+[sam]
+enabled = true
+address = 0.0.0.0
+port = 7656
+
+[upnp]
+enabled = false
+
+[reseed]
+verify = true
+
+[limits]
+# transittunnels = 2500