Document double-colon notation when autolink to Erlang entities (#2161)

Author: eksperimental

README.md

@@ -227,9 +227,9 @@ ExDoc for Elixir and Erlang will automatically generate links across modules and
 
 ### Elixir
 
-ExDoc will automatically link modules, functions, types or callbacks defined in your project and its dependencies (including Erlang and Elixir). ExDoc will automatically link to it at the dependency's documentation at [hexdocs.pm](https://hexdocs.pm/). The link can be configured by setting `docs: [deps: [my_dep: "https://path/to/docs/"]]` in your `mix.exs`.
+ExDoc will automatically link modules, functions, types or callbacks defined in your project and its dependencies (including Erlang and Elixir). ExDoc will automatically link to the dependency's documentation at [hexdocs.pm](https://hexdocs.pm/). The link can be configured by setting `docs: [deps: [my_dep: "https://path/to/docs/"]]` in your `mix.exs`.
 
-ExDoc supports linking to modules (`` `MyModule` `` and `` `m:MyModule` ``), functions (`` `MyModule.function/1` ``), types (`` `t:MyModule.type/2` ``) and callbacks (`` `c:MyModule.callback/3` ``). If you want to link a function, type or callback in the current module, you may skip the module name, for example: `` `function/1` ``.
+ExDoc supports linking to modules (`` `MyModule` `` and `` `m:MyModule` ``), functions (`` `MyModule.function/1` ``), types (`` `t:MyModule.type/2` ``) and callbacks (`` `c:MyModule.callback/3` ``). If you want to link a function, type or callback in the current module, you may skip the module name, for example: `` `function/1` ``. Similarly, you can automatically link to Erlang modules (`` `m::my_module` ``), functions (`` `:my_module.function/1` ``), types (`` `t::my_module.type/2` ``) and callbacks (`` `c::my_module.callback/3` ``) (since Erlang modules in Elixir start with `:`, note the double colon in some cases).
 
 You can also use custom text, such as `` [custom text](`MyModule.function/1`) ``. Link to extra pages using the syntax `` [Up and running](Up and running.md) ``. The final link will be automatically converted to `up-and-running.html`.