switch to pretty URLs and add canonical link tags

Remove uglyURLs so that paths no longer carry the unnecessary
.html extension, which only adds length and makes URLs harder
to read and type.

Add baseURL and canonical link tags so that search engines can
identify the page and URL as authoritative.

Use relURL for the banner image so it resolves correctly under
pretty URL paths.

Author: ritorhymes

hugo.yml

@@ -1,8 +1,8 @@
 ---
+baseURL: https://gitgitgadget.github.io/
 languageCode: en
 title: GitGitGadget
 relativeURLs: true
-uglyURLs: true
 disableKinds:
 - taxonomy
 markup:

layouts/_default/baseof.html

@@ -4,6 +4,7 @@
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <title>{{ .Title }}</title>
+    <link rel="canonical" href="{{ .Permalink }}">
     <link rel="icon" href="{{ relURL "favicon.ico" }}">
     {{- $style := resources.Get "sass/main.scss" | resources.ExecuteAsTemplate "main.scss" . | css.Sass }}
     <link rel="stylesheet" href="{{ $style.RelPermalink }}">

layouts/partials/banner.html

@@ -1,5 +1,5 @@
 {{- define "partials/logo.html" -}}
-<img src="images/gitgitgadget-explanation.png"  alt="An arrow from git logo to an envelop with git logo. The arrow is labelled by famous Inspector Gadget hat."/>
+<img src="{{ relURL "images/gitgitgadget-explanation.png" }}"  alt="An arrow from git logo to an envelop with git logo. The arrow is labelled by famous Inspector Gadget hat."/>
 {{- end -}}
 {{- define "partials/subtitle.html" -}}
 <big>GitGitGadget</big><br />