New login screen (#1331)

* wip

* feat: first draft of auth.config

* chore: auth methodS

* chore: styling

* styling, styling, styling

* feat: Auth notices

* chore: Remove server-rendered pages, move shared/components -> components

* lint

* cleanup

* cleanup

* fix: Remove unused component

* fix: Ensure env variables in prod too

* style tweaks

* fix: Entering SSO email into login form fails
fix: Tweak language around guest signin

app/components/Time.js

@@ -0,0 +1,55 @@
+// @flow
+import * as React from "react";
+import Tooltip from "components/Tooltip";
+import distanceInWordsToNow from "date-fns/distance_in_words_to_now";
+import format from "date-fns/format";
+
+let callbacks = [];
+
+// This is a shared timer that fires every minute, used for
+// updating all Time components across the page all at once.
+setInterval(() => {
+  callbacks.forEach(cb => cb());
+}, 1000 * 60);
+
+function eachMinute(fn) {
+  callbacks.push(fn);
+
+  return () => {
+    callbacks = callbacks.filter(cb => cb !== fn);
+  };
+}
+
+type Props = {
+  dateTime: string,
+  children?: React.Node,
+};
+
+class Time extends React.Component<Props> {
+  removeEachMinuteCallback: () => void;
+
+  componentDidMount() {
+    this.removeEachMinuteCallback = eachMinute(() => {
+      this.forceUpdate();
+    });
+  }
+
+  componentWillUnmount() {
+    this.removeEachMinuteCallback();
+  }
+
+  render() {
+    return (
+      <Tooltip
+        tooltip={format(this.props.dateTime, "MMMM Do, YYYY h:mm a")}
+        placement="bottom"
+      >
+        <time dateTime={this.props.dateTime}>
+          {this.props.children || distanceInWordsToNow(this.props.dateTime)}
+        </time>
+      </Tooltip>
+    );
+  }
+}
+
+export default Time;