feat: Adding series to the theme

Kenneth

15.01.2021 d530d03761514d90de059ca005063d447f50460c

 exampleSite/config/_default/config.toml

@@ -21,4 +21,9 @@
[markup]
    [markup.goldmark]
        [markup.goldmark.renderer]
        unsafe=true
        unsafe=true

[taxonomies]
    category = "categories"
    series = "series"
    tag = "tags"