Print downloaded file size.

[smimram]

Since we have the downloaded file size, let's print it: it is useful in order to estimate how much downloading is still required (ideally we should have a progress bar, but this is already an improvement).

[valerio-bozzolan]

I tried this patch on my computer and it just works as expected. Example output on my computer:

/download.py "https://example.com/playback/presentation/2.0/playback.html?meetingId=e420724e96d095a1510420cdc783fa50f0aee67a-1678267846906" test

Downloading https://example.com/presentation/e420724e96d095a1510420cdc783fa50f0aee67a-1678267846906/slides_new.xml (8560 bytes)...
Downloading https://example.com/presentation/e420724e96d095a1510420cdc783fa50f0aee67a-1678267846906/video/webcams.webm (373897405 bytes)...

I suggest in merging it.

(I'm not the maintainer)

[valerio-bozzolan]

Premising that I've done some code review, and I'm merging what I like in this fork:

https://github.com/valerio-bozzolan/bbb-render

Hoping to be useful, this pull request was merged in that fork, at this point:

https://github.com/valerio-bozzolan/bbb-render/commit/b427d05f43accb172d02b9997ddc6ea82e74456a