Embed Zammad support form into contacts page

.gitmodules

@@ -7,3 +7,6 @@
 [submodule "assets/vendor/MathJax"]
 	path = assets/vendor/MathJax
 	url = https://github.com/mathjax/MathJax.git
+[submodule "assets/vendor/jquery"]
+	path = assets/vendor/jquery
+	url = https://github.com/jquery/jquery.git

_includes/contact_form.html

+<div id="feedback-form">form will be placed in here</div>
+
+<script type="text/javascript"
+        src="{{ site.directory.vendor | append: 'jquery/dist/jquery.min.js' | strip | relative_url }}">
+</script>
+<script id="zammad_form_script" src="https://hifis-help.hzdr.de/assets/form/form.js"></script>
+
+<script>
+$(function () {
+    $('#feedback-form').ZammadForm({
+        messageTitle: 'Contact HIFIS',
+        messageSubmit: 'Submit',
+        messageThankYou: 'Thank you for your request (#%s). You will hear from us soon!',
+        attachmentSupport: true,
+        noCSS: true,
+    });
+});
+</script>

assets/css/contact.scss

+---
+---
+
+@import  "bootstrap_variables";
+
+@import "assets/vendor/bootstrap/scss/functions";
+@import "assets/vendor/bootstrap/scss/variables";
+@import "assets/vendor/bootstrap/scss/mixins";
+
+@import "assets/vendor/bootstrap/scss/buttons";
+
+.form-control {
+    width: -webkit-fill-available;
+    width: -moz-available;
+}
+
+.btn {
+    @extend .btn-primary;
+}

assets/css/hifis.scss

@@ -31,6 +31,7 @@
 @import "assets/vendor/bootstrap/scss/buttons";
 @import "assets/vendor/bootstrap/scss/card";
 @import "assets/vendor/bootstrap/scss/close";
+@import "assets/vendor/bootstrap/scss/forms";
 @import "assets/vendor/bootstrap/scss/jumbotron";
 @import "assets/vendor/bootstrap/scss/toasts";
 @import "assets/vendor/bootstrap/scss/tooltip";

jquery @ e1cffdef

+Subproject commit e1cffdef277fcf543833a20d28cbadcd000ebece

contact.md

@@ -5,9 +5,13 @@ layout: default
 excerpt:
     Contact to HIFIS Office.
 lang: en
-lang_ref: contact    
+lang_ref: contact
+additional_css:
+  - contact.css
 ---
 
+{% include contact_form.html %}
+
 ## Questions to this website? Contact us!
 {:.text-success}
 #### Uwe Jandt