Output formats summary

[valentinsulzer]

General issue to summarize the output formats. We are making good progress with the backend and reading citations from different parts of the code. We should think about standardising the way citations are stored (e.g. convert everything to bibtex), and then providing tools to output in different formats:

• citeproc and CSL (Use citeproc and CSL to allow references to be formatted according to different standards #44)
• Citation file format (Convert between bibtex and citation file format #14)
• CodeMeta (Convert between bibtex and citation file format #14)
• Standard citation formats? (Harvard, APA, etc)