Documentation links on corpora lead to non-existing pages

[albbas]

On the page https://giellalt.github.io/CorpusResources.html, the links to corpus documentation pages do not work, e.g. Arabic (converted) points to https://giellalt.github.io/corpus-ara/

[Trondtr]

Missing for that to work is a template repository parallel to https://github.com/giellalt/template-lang-und and https://github.com/giellalt/template-dict-undS-undT, a template-corpus-und and a template-corpus-und-orig.

Note also that the -orig corora are marked as (undefined) in the geographic and language family sections, in the (initial) Overview section they are correctly marked.