rValue history of germany

[PatrickHaussmann]

this would fix #95

There are a few things i am not sure about:

1. is the name /germany/history/rValue ok?
2. the first 4 days have a r-value of null. Should we remove them?
3. lastUpdate is set to now. Is there a better way get the lastUpdate value

[Rubber1Duck]

1. is the name `/germany/history/rValue` ok?

2. the first 4 days have a `r-value` of `null`. Should we remove them?

3. `lastUpdate` is set to `now`. Is there a better way get the `lastUpdate` value

1. think thats okay
2. yes, that makes sense.
3. maybe as in vaccination.ts

const response = await axios.get(
    `https://www.rki.de/DE/Content/InfAZ/N/Neuartiges_Coronavirus/Daten/Impfquotenmonitoring.xlsx?__blob=publicationFile`,
    {
      responseType: "arraybuffer",
    }
  );
  const data = response.data;
  const lastModified = response.headers["last-modified"];
  const lastUpdate = lastModified != null ? new Date(lastModified) : new Date();

that should work .....

[PatrickHaussmann]

if we would have: const lastUpdate = history[history.length - 1].date;

then it would be in line with what we return in the function getRValue. Alternatively, we could also get it from the headers in getRValue. what is your take on this?

[Rubber1Duck]

both should be the same and it is a good idea to take it from the header! My mind ....

[Rubber1Duck]

/germany/history/rValue/:days would be very nice!

[PatrickHaussmann]

/germany/history/rValue/:days would be very nice!

I am already in the process :)

[PatrickHaussmann]

i am very sorry that it is not clear to me. but what should i change/add in README.md?

[Rubber1Duck]

God job! for me that looks all fine!

[Rubber1Duck]

is replaced by new PR #494