Add a rel option to social registers (#596)

* Add a `rel` option to social registers

Fixes #417

* Fix typo

README.md

@@ -135,7 +135,7 @@ In order to register a service to be used, user must add an `ananke_socials` par
 - name*: It matches the built-in service reference (Ex: twitter, github)
 - url*: The url of the handle's profile on the service (Ex: https://twitter.com/theNewDynamic, https://github.com/
 theNewDynamic)
-
+- rel: Optional. Allows to add a `rel` attribute to the follow link. Useful for Mastodon verification which requires a `rel="me"` on the link.
 ```yaml
 params:
   ananke_socials:
@@ -143,6 +143,9 @@ params:
     url: https://twitter.com/theNewDynamic
   - name: github
     url: https://github.com/theNewDynamic
+  - name: mastodon
+    url: https://social.example.com/@username
+    rel: me
 ```
 
 If user needs to overwrite default `color` and `label` of the service, they simply need to append the following to the entry:

layouts/partials/social-follow.html

@@ -1,7 +1,7 @@
 {{ $socials := where (partialCached "func/socials/Get" "socials/Get") "follow" "!=" false }}
 <div class="ananke-socials">
   {{ range $socials }}
-    <a href="{{ .url }}" target="_blank" class="{{ .name }} ananke-social-link link-transition stackoverflow link dib z-999 pt3 pt0-l {{ cond (eq $.Site.Language.LanguageDirection "rtl") "ml1" "mr1" }}" title="{{ .label }} link" rel="noopener" aria-label="follow on {{ .label }}——Opens in a new window">
+    <a href="{{ .url }}" target="_blank" {{ with .rel }} rel="{{ . }}" {{ end }} class="{{ .name }} ananke-social-link link-transition stackoverflow link dib z-999 pt3 pt0-l {{ cond (eq $.Site.Language.LanguageDirection "rtl") "ml1" "mr1" }}" title="{{ .label }} link" rel="noopener" aria-label="follow on {{ .label }}——Opens in a new window">
       {{ with .icon }}
         <span class="icon">{{ . }}</span>
       {{ else }}