Add helper components for UI

Changes:
- Extracted Copyright from LoginDialog file to its own
- Added some helper components
- Removed unnecessary setup from welcome animation
- Added custom React type for svg element
- Fixed ThemeDemonstrator

GitLab: #12
Change-Id: Ie7158520983dab5c7069f179b6f9531b5106ba85
diff --git a/client/src/components/Copyright.tsx b/client/src/components/Copyright.tsx
new file mode 100644
index 0000000..a89855f
--- /dev/null
+++ b/client/src/components/Copyright.tsx
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2022 Savoir-faire Linux Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+import { Link } from '@mui/material';
+import Typography from '@mui/material/Typography';
+
+// TODO: Choose on which pages to put this.
+export default function Copyright() {
+  return (
+    <Typography variant="body2" color="textSecondary" align="center" sx={{ position: 'absolute', bottom: 0, left: 0 }}>
+      {'Copyright © 2016-'}
+      {new Date().getFullYear()}
+      {' Savoir-faire Linux Inc.'}
+      <Link color="inherit" href="https://jami.net/">
+        Jami.net
+      </Link>{' '}
+      {'.'}
+    </Typography>
+  );
+}