🎨 Add fancy html emails

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

lib/mobilizon_web/templates/email/report.text.eex

@@ -1,19 +0,0 @@
-<%= gettext "New report from %{reporter} on %{instance}", reporter: @report.reporter.preferred_username, instance: @instance %>
-
---
-
-<% if @report.event do %>
-    <%= gettext "Event: %{event}", event: @report.event.title %>
-<% end %>
-
-<%= for comment <- @report.comments do %>
-<%= gettext "Comment: %{comment}", comment: comment.text %>
-<% end %>
-
-<% if @report.content do %>
-<%= gettext "Reason: %{content}", event: @report.content %>
-<% end %>
-
-View the report: <%= moderation_report_url(MobilizonWeb.Endpoint, :index, @report.id) %>
-
-