Simplify comparison of project definitions

[donkirkby]

In step 4 of the release instructions in CONTRIBUTING.md, it says to download the project definitions from QAI, and compare them with the source code in projects.json and project_scoring.json. However, it looks like some recent changes have made that comparison harder.

• The entries in the current files don't seem to be sorted, and the downloaded version is sorted. Add an option to just sort the current files without downloading them, just to help with comparisons.
• The genotype_references key isn't downloaded, and might not be in the database at all. Either document that it can be ignored, or figure out where to download it from.
• It looks like the extra references for the HIVGHA project (HIV1-CRF02_AG-GH-AB286855-seed and HIV1-CRF06_CPX-GH-AB286851-seed) are included in more places than they should be. Is that a bug in the download script?