Recommend a full installation of erlang on Fedora (elixir-lang#1499)

There was a person in the Elixir slack today that had trouble trying to use a dependency that depended on xmerl. The solution for him was `sudo dnf install erlang-xmerl` (although `sudo dnf install erlang` would have been better). I've also seen Fedora users having trouble running ElixirLS if they don't have a full installation of erlang because they don't have the `erlang-dialyzer` package: elixir-lsp/elixir-ls#231 Looking at the latest version of the elixir package for erlang we can see that the "Requires" list is much smaller than the "BuildRequires" list: https://src.fedoraproject.org/rpms/elixir/blob/1118b2d2b1e973ba8188f7e479db174850697b2f/f/elixir.spec Therefore, for typical Elixir development I believe it is important for Fedora users to have a full installation of Erlang.

Author: axelson

install.markdown

@@ -41,7 +41,7 @@ If your distribution contains an old Elixir/Erlang version, see the sections bel
 * Run: `yum install elixir`
 
 -**Fedora 22 (and newer)**
-* Run `dnf install elixir`
+* Run `dnf install elixir erlang`
 
 -**Gentoo**
 * Run: `emerge --ask dev-lang/elixir`