[candidate_list] Translate candidate_list module

[driusan]

This translates the candidate list module as an example of how to do localization of a loris module that is written in React with class based components.

JSON files are generated from the same .po files used by the PHP side of file, which are then imported into the i18next resources. They are generated at compile time with the i18next-conv package. Modules (in this case candidate_list) must call the addResourceBundle method of i18next to add the strings which are specific to their module.

This example uses the withTranslation HOC, but functional components can use the useTranslation hook instead.

Note that in this PR I only translated the strings from the candidate_list module itself used by the filters/headers to serve as an example. There are other strings which come from components in the jsx/ directory which are shared across all modules. Those will be in other PRs since they are a one-time effort for all modules.