Add relative_url filter for preview context

Signed-off-by: Benoit Donneaux <benoit@leastauthority.com>

src/_includes/head/custom.html

@@ -1,5 +1,5 @@
 <!-- start custom head snippets -->
 
-<link href="/assets/images/favicon.ico" rel="shortcut icon" type="image/x-icon">
+<link href="{{ /assets/images/favicon.ico | relative_url }}" rel="shortcut icon" type="image/x-icon">
 
 <!-- end custom head snippets -->

src/_posts/2020-09-08-welcome.md

@@ -6,7 +6,7 @@ excerpt: "Welcome to Dummy Jekyll"
 header:
   teaser: /assets/images/posts/unsplash-welcome.jpg
 gallery:
-  - image_path: assets/images/posts/unsplash-welcome.jpg
+  - image_path: /assets/images/posts/unsplash-welcome.jpg
     alt: "welcome"
 ---
 {% include gallery %}

src/_posts/2020-09-09-post-1.md

@@ -6,7 +6,7 @@ excerpt: "This is a generic post."
 header:
   teaser: /assets/images/posts/unsplash-post.jpg
 gallery:
-  - image_path: assets/images/posts/unsplash-post.jpg
+  - image_path: /assets/images/posts/unsplash-post.jpg
     alt: "post"
 ---
 {% include gallery %}

src/_posts/2020-09-09-post-2.md

@@ -6,7 +6,7 @@ excerpt: "This is a generic post."
 header:
   teaser: /assets/images/posts/unsplash-post.jpg
 gallery:
-  - image_path: assets/images/posts/unsplash-post.jpg
+  - image_path: /assets/images/posts/unsplash-post.jpg
     alt: "post"
 ---
 {% include gallery %}

src/_posts/2020-09-09-post-3.md

@@ -6,7 +6,7 @@ excerpt: "This is a generic post."
 header:
   teaser: /assets/images/posts/unsplash-post.jpg
 gallery:
-  - image_path: assets/images/posts/unsplash-post.jpg
+  - image_path: /assets/images/posts/unsplash-post.jpg
     alt: "post"
 ---
 {% include gallery %}

src/index.html

@@ -17,14 +17,14 @@ excerpt: "Tahoe-LAFS is a Free and Open decentralized cloud storage system.
 documentation:
   - title: "Welcome <i>The</i> Least-Authority File Store"
 documentation_list:
-  - image_path: /assets/images/overview.png
+  - image_path: {{ /assets/images/overview.png | relative_url }}
     alt: "overview"
     title: "Overview"
     excerpt: "A one-page summary explains the unique properties of this system."
     url: "https://tahoe-lafs.readthedocs.io/en/latest/about-tahoe.html"
     btn_label: "Read More"
     btn_class: "btn--primary"
-  - image_path: assets/images/manual.jpg
+  - image_path: {{ /assets/images/manual.jpg | relative_url }}
     image_caption: "Image courtesy of [Unsplash](https://unsplash.com/)"
     alt: "manual"
     title: "Manual"
@@ -32,7 +32,7 @@ documentation_list:
     url: "https://tahoe-lafs.readthedocs.io/"
     btn_label: "Read More"
     btn_class: "btn--primary"
-  - image_path: /assets/images/wiki.jpg
+  - image_path: {{ /assets/images/wiki.jpg | relative_url }}
     image_caption: "Image courtesy of [Unsplash](https://unsplash.com/)"
     alt: "wiki"
     title: "Wiki"
@@ -44,7 +44,7 @@ contribute:
   - title: "Get Involved"
     excerpt: ""
 contribute_list:
-  - image_path: assets/images/mailing.jpg
+  - image_path: {{ /assets/images/mailing.jpg | relative_url }}
     image_caption: "Image courtesy of [Unsplash](https://unsplash.com/)"
     alt: "mailing"
     title: "Mailing list"
@@ -52,7 +52,7 @@ contribute_list:
     url: "https://lists.tahoe-lafs.org/mailman/listinfo/tahoe-dev"
     btn_label: "Subscribe"
     btn_class: "btn--primary"
-  - image_path: /assets/images/messaging.jpg
+  - image_path: {{ /assets/images/messaging.jpg | relative_url }}
     image_caption: "Image courtesy of [Unsplash](https://unsplash.com/)"
     alt: "messaging"
     title: "Instant messaging"
@@ -60,7 +60,7 @@ contribute_list:
     url: "https://libera.chat/"
     btn_label: "Chat"
     btn_class: "btn--primary"
-  - image_path: /assets/images/meet.jpg
+  - image_path: {{ /assets/images/meet.jpg | relative_url }}
     image_caption: "Image courtesy of [Unsplash](https://unsplash.com/)"
     alt: "meet"
     title: "Meeting"
@@ -72,7 +72,7 @@ blog:
   - title: "News"
     excerpt: "Find here under a list of the latest articles on the subjects that matter for us."
 about:
-  - image_path: /assets/images/volunteers.jpg
+  - image_path: {{ /assets/images/volunteers.jpg | relative_url }}
     image_caption: "Image courtesy of [Unsplash](https://unsplash.com/)"
     alt: "about image"
     title: "Volunteers"
@@ -96,10 +96,10 @@ about:
   <div class="grid__item">
     <article class="archive__item" itemscope itemtype="https://schema.org/CreativeWork">
       <div class="archive__item-teaser">
-        <img src="{{post.header.teaser}}" alt="">
+        <img src="{{ post.header.teaser | relative_url }}" alt="">
       </div>
       <h2 class="archive__item-title" itemprop="headline">
-        <a href="{{ post.url }}" rel="permalink">{{ post.title }}</a>
+        <a href="{{ post.url | relative_url }}" rel="permalink">{{ post.title }}</a>
       </h2>
       <p class="archive__item-excerpt" itemprop="description">{{ post.excerpt }}</p>
     </article>