Merge pull request #81 from jvalecillos/patch/post-list-hugo-v0.57.0

This should fix the issue with Hugo's breaking changes since v0.57 as mentioned in gohugoio/hugoThemes#678.
- adjusted post list for Hugo v0.57.0
Credits: @jvalecillos.

layouts/index.html

@@ -4,7 +4,7 @@
 
 {{ define "content" }}
   <div class="post-list">
-    {{ $paginator := .Paginate (where .Data.Pages "Type" "posts") }}
+    {{ $paginator := .Paginate (where .Site.RegularPages "Type" "in" site.Params.mainSections) }}
     {{ range $paginator.Pages }}
       {{ if .Draft }}
         {{ .Scratch.Set "draftPage" true }}