This PR adds the default Hugo taxonomies configuration in the second config of the HugoBasicExample.
This PR will fix a number of theme demos that currently require the default Hugo taxonomies.
For example the [Plain Blog](https://themes.gohugo.io/plain-blog/) theme demo will generate once again after this PR is merged.
Some themes like for example [Hyde Hyde](https://github.com/htr3n/hyde-hyde/tree/master/exampleSite/content) have their content files under a section called `posts`
Currently the index page of these theme demos renders empty because there is no `posts` section in the HugoBasicExample.
So to fix this I have added a symlink called `posts` that points to the content files located under the `post` of the HugoBasicExample repo.
In theory this workaround can be used for other sections as well like e.g. `articles` etc (as long as it doesn't break anything).
Commit 93a7b4c had the side effect of causing existing theme demos that rely on the HugoBasicExample to display the French language posts.
So with this PR the French translation of the posts is disabled by default, to keep things for existing demos as before.
**NOTE**
When we are done with overhauling the HugoBasicExample we will need to add documentation in its README.
For example in this case we will need to state that authors who wish to have a multilingual theme demo will need to remove `disableLanguages = ["fr"]` from the exampleSite config.
This reverts commit 4e47e94a69.
A [great number](https://app.netlify.com/sites/hugothemes/deploys/5c6936d1dddaef000819a6e8) of theme demos on the website broke because of this commit due to the following:
- Series is on the predefined frontmatter variable lists due to its use in the internal opengraph template.
- Series is predefined as an array whereas I entered it as a string.
- Also series needs to be defined as a Taxonomy in the config of an exampleSite. Since the config is inherited by theme authors if they have not defined the series taxonomy then their demo will again break.
**NOTE**
I will be more rigorous with testing before sending more PRs.
cc: @digitalcraftsman
Hugo ouputs an error like:
ERROR: 2014/11/19 Walker: lstat /path/to/HugoBasicExample/layouts: no such file or directory
when testing a new theme against this repo, unless the layouts folder is created first
Tested with hugo built from commit master (on commit 728d0fa32cb666264045783518cc6ded5c78f246)
