[#396] Updated `ex_doc` version spec. Updated README to reflect Elixir version.

README.md

@@ -30,7 +30,7 @@ While we don't provide docker files, other people have written very good ones. T
 ### Dependencies
 
 * Postgresql version 9.6 or newer
-* Elixir version 1.5 or newer. If your distribution only has an old version available, check [Elixir's install page](https://elixir-lang.org/install.html) or use a tool like [asdf](https://github.com/asdf-vm/asdf).
+* Elixir version 1.7 or newer. If your distribution only has an old version available, check [Elixir's install page](https://elixir-lang.org/install.html) or use a tool like [asdf](https://github.com/asdf-vm/asdf).
 * Build-essential tools
 
 ### Configuration

mix.exs

@@ -71,7 +71,7 @@ defp deps do
       {:crypt,
        git: "https://github.com/msantos/crypt", ref: "1f2b58927ab57e72910191a7ebaeff984382a1d3"},
       {:cors_plug, "~> 1.5"},
-      {:ex_doc, "> 0.18.3 and < 0.20.0", only: :dev, runtime: false},
+      {:ex_doc, "~> 0.19", only: :dev, runtime: false},
       {:web_push_encryption, "~> 0.2.1"},
       {:swoosh, "~> 0.20"},
       {:gen_smtp, "~> 0.13"},