Introduce avatar and banner and fetch Gravatar to fill avatar during registration

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

typo

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

Rename avatar to avatar_url, same with header.

Add a comment to explain why the tweak with HTTPoison and TLS1.2

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

Rename avatar to avatar_url

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

rename old avatar properties in front-end to avatar_url

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

fix change gravatar from ?d= to ?default=

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

reorganize aliases and imports

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

set avatar url only when gravatar exists, add a test for that case

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

mix.exs

@@ -44,7 +44,6 @@ defmodule Eventos.Mixfile do
       {:phoenix_ecto, "~> 3.2"},
       {:postgrex, ">= 0.0.0"},
       {:phoenix_html, "~> 2.10"},
-      {:phoenix_live_reload, "~> 1.0", only: :dev},
       {:gettext, "~> 0.11"},
       {:cowboy, "~> 1.0"},
       {:guardian, "~> 1.0"},
@@ -58,10 +57,14 @@ defmodule Eventos.Mixfile do
       {:geo_postgis, "~> 1.0"},
       {:timex, "~> 3.0"},
       {:timex_ecto, "~> 3.0"},
+      {:icalendar, "~> 0.6"},
+      {:exgravatar, "~> 2.0.1"},
+      {:httpoison, "~> 1.0"},
+      # Dev and test dependencies
+      {:phoenix_live_reload, "~> 1.0", only: :dev},
       {:ex_machina, "~> 2.1", only: :test},
       {:credo, "~> 0.8", only: [:dev, :test], runtime: false},
       {:excoveralls, "~> 0.8", only: :test},
-      {:icalendar, "~> 0.6"},
       {:ex_doc, "~> 0.16", only: :dev, runtime: false},
       {:mix_test_watch, "~> 0.5", only: :dev, runtime: false},
       {:ex_unit_notifier, "~> 0.1", only: :test}