Update website so it works with the latest version of TypeScript

[26]

The current version of screensy-website/screensy.ts does not compile with the latest version of TypeScript (4.3.2). This is related to #5, which was fixed by requiring an older version in the Dockerfile. This fix is not optimal, since it makes it harder to upgrade or to install screensy without using Docker.

[Stef-Gijsberts]

The current version of screensy-website/screensy.ts does not compile with the
latest version of TypeScript (4.3.2).

Indeed, compilation with TypeScript 4.3.3 fails with the following error:

screensy.ts:181:52 - error TS2339: Property 'maxFramerate' does not exist on
type 'RTCRtpEncodingParameters'.

181 rtcSendParameters.encodings[0].maxFramerate = 30;

This is most likely caused by the effort to remove types and features which
are not used in any browser. Indeed, at the time of writing,
RTCRtpEncodingParameters.maxFramerate is not used by any browser according to
caniuse.

We have two options:

1. Remove the line.
2. Add a // @ts-ignore. This would cause the option to have effect in the future
   if browser developers choose to implement it.

I prefer the first option, removing the line. Just for simplicity, and because we
don't know what effects the property would exactly have were browser developers
to implement it.

[Stef-Gijsberts]

Indeed, at the time of writing, RTCRtpEncodingParameters.maxFramerate is
not used by any browser according to caniuse.

I however just realized that this statement is not proven to be true. For the
Safari browser, the support info is "Unknown". We might have to do a little
testing to see if the property has any effect on Safari.

[Stef-Gijsberts]

Now, two days later, caniuse does report support of
RTCRtpEncodingParameters.maxFramerate on Safari. Therefore, I think we should
keep the line. Thoughts, @26?

We will have to add a // @ts-ignore then, so that TypeScript 4.3 can be used
to compile screensy.

[26]

That sounds good to me.

[Stef-Gijsberts]

This was merged into development in ccfe9c4 and will be included in the next release.

(link to the specific line)