Add email signup feature

templates/email_signups/create.rs.html

@@ -0,0 +1,9 @@
+@use crate::template_utils::*;
+@use crate::templates::base;
+
+@(ctx: BaseContext)
+
+@:base(ctx, i18n!(ctx.1, "Registration"), {}, {}, {
+    <h1>@i18n!(ctx.1, "Check your inbox!")</h1>
+    <p>@i18n!(ctx.1, "We sent a mail to the address you gave us, with a link for registration.")</p>
+})