add support for impressum page (alshedivat#172)

* add support for impressum page

* Update _config.yml

Co-authored-by: Maruan <alshedivat@users.noreply.github.com>

Co-authored-by: Maruan <alshedivat@users.noreply.github.com>

Author: junghans

_config.yml

@@ -17,6 +17,7 @@ footer_text: >
 url:  # the base hostname & protocol for your site
 baseurl: /al-folio # the subpath of your site, e.g. /blog/
 last_updated: false # set to true if you want to display last updated in the footer
+impressum_path:  # set to path to include impressum link in the footer, use the same path as permalink in a page, helps to conform with EU GDPR
 
 # -----------------------------------------------------------------------------
 # Layout

_includes/footer.html

@@ -3,6 +3,9 @@
   <div class="container mt-0">
     &copy; Copyright {{ site.time | date: '%Y' }} {{ site.first_name }} {{ site.middle_name }} {{ site.last_name }}.
     {{ site.footer_text }}
+    {% if site.impressum_path %}
+    <a href="{{ site.url }}{{ site.baseurl }}{{ site.impressum_path }}">Impressum</a>.
+    {% endif %}
     {% if site.last_updated %}
     Last updated: {{ "now" | date: '%B %d, %Y' }}.
     {% endif %}
@@ -13,6 +16,9 @@
   <div class="container">
     &copy; Copyright {{ site.time | date: '%Y' }} {{ site.first_name }} {{ site.middle_name }} {{ site.last_name }}.
     {{ site.footer_text }}
+    {% if site.impressum_path %}
+    <a href="{{ site.url }}{{ site.baseurl }}{{ site.impressum_path }}">Impressum</a>.
+    {% endif %}
     {% if site.last_updated %}
     Last updated: {{ "now" | date: '%B %d, %Y' }}.
     {% endif %}