Create Occitan locale (luizdepra#921)

### Prerequisites

Put an `x` into the box(es) that apply:

- [ ] This pull request fixes a bug.
- [ x] This pull request adds a feature.
- [ ] This pull request introduces breaking change.

### Description

This PR adds the Occitan language

Co-authored-by: Luiz F. A. de Prá <[email protected]>

Author: ensag-dev

Diff for: i18n/oc.toml

@@ -0,0 +1,64 @@
+[categories]
+one = "categoria"
+other = "categorias"
+
+[tags]
+one = "etiqueta"
+other = "etiquetas"
+
+[series]
+one = "serias"
+other = "serias"
+
+[authors]
+one = "autor"
+other = "autors"
+
+[posts]
+other = "publicacions"
+
+[reading_time]
+one = "Una minuta de lector"
+other = "{{ .Count }} minutas de lectura"
+
+[page_not_found]
+other = "Pagina pas trobada"
+
+[page_does_not_exist]
+other = "O planhèm, aquesta pagina existís pas."
+
+[head_back]
+other = "Podètz tornar a <a href=\"{{ . }}\">l'acuèlh</a>."
+
+[licensed_under]
+other = "Licéncia jos"
+
+[powered_by]
+other = "Propulsat per"
+
+[see_also]
+other = "Vejatz tanben"
+
+[note]
+other = "nòta"
+
+[tip]
+other = "astúcia"
+
+[example]
+other = "exemple"
+
+[question]
+other = "question"
+
+[info]
+other = "info"
+
+[warning]
+other = "avertiment"
+
+[error]
+other = "error"
+
+[link_to_heading]
+other = "Ligam a l'entèsta"