Theme update (#553)

* Start to update the theme

- Ligther colors
- No more border radius
- Buttons are now always colored
- Start to redesign the post page (according to the Figma mockups)

* Fix build script: it now recompiles everytime a scss file changed

* Make sure the article illustrations are not too big

* Make articles wider (70 characters)

* Better contrast between gray shades

* Various improvements

* Better mobile style

* New style for the footer

* Improve comment style

* Better responsiveness again

* Limit the size of the article cover

* Last details?

- Improve buttons on the media page
- Improve lists

* Pin the stdweb version that we use

It changed because I removed Cargo.lock to handle a merge conflict

I could have updated cargo web too, but it mean I should have re-built
the CI docker image and it was taking forever.

* Better contrast for links in the header of the article

* Add a basic privacy policy

* Remove "also"

* Fix a few issues

- Don't watch static/css in build.rs
- Another shade of white
- Remove useless margin rule for error messages

templates/blogs/details.rs.html

@@ -55,7 +55,7 @@
                     <a href="@uri!(blogs::edit: name = &blog.fqn)" class="button">@i18n!(ctx.1, "Edit")</a>
                 }
             </div>
-            
+
             <main class="user-summary">
                 <p>
                     @i18n!(ctx.1, "There's one author on this blog: ", "There are {0} authors on this blog: "; authors.len())
@@ -74,7 +74,7 @@
         @if posts.is_empty() {
             <p>@i18n!(ctx.1, "No posts to see here yet.")</p>
         }
-        <div class="cards spaced">
+        <div class="cards">
             @for article in posts {
                 @:post_card(ctx, article)
             }