v0.0.6

Sometimes, when downloading information for large numbers of KOs from the KEGG API, the API will forbid downloads because there are too many requests (see this issue in AMON). This isn't an ideal fix, but with these updates, if the asynchronous requests are forbidden, the KOs will be downloaded sequentially instead of asynchronously. This is quite a bit slower, but it gets around the issue.

The request rate limit of the API isn't clearly laid out, so this is what we have for now. Perhaps a future approach should have some batch size limit for asynchronous requests.