Progress bar, Changing the Activity type to Listening and Secondary Button support

[fumiichan]

This PR contains the following changes:

• Updated DiscordRichPresence to latest version in NuGet.
• Removed "Show Remaining time" option in favour of Progress Bar display
• Changed Activity Type to "Listening" (Closes Add "Listening to" as a option instead of default "Playing" #242)
• Adds support for a second button (Closes Second custom button #235)
• Updated RestSharp to non-vulnerable version
• Do not display progress bar when duration value is -1.
• Added support to update rich presence when album art is ready
• Moved to FreeImageHost instead of imgur. Which should be fix the cover art issues for the foreseeable future (Closes Recent Discord update broke cover images once again #253 and Closes Album Covers suddenly not showing up #256)

For testers, here's a prebuilt with up-to-date changes:
https://github.com/doujincafe/DiscordBee/releases/tag/v3.2.0-final

Preview:

[Chinhsss]

Placeholder in album cover seem like also appear in progress bar?

[fumiichan]

It's Discord's issue or by design.

[Chinhsss]

It's Discord's issue or by design.
Original DiscordBee doesn't have that issue, so i think it might be something with the progress bar

[fumiichan]

That happens only when Activity type is configured to Listening.

Other clients for example also does this:

[Chinhsss]

Album Cover seem like broken again?

[LinkLegend819]

The nuget version of DiscordRichPresence was updated; is there any word on getting this updated and merged?

[fumiichan]

This is final release from me. This time, this uses FreeImageHost instead of Imgur and also updated Discord Rich Presence to latest version.

https://github.com/doujincafe/DiscordBee/releases/tag/v3.2.0-final

[catgirlmutant]

album arts still don't load for me for some reason </3

[fumiichan]

Reset everything to defaults. Delete caches and configuration files and try again.

[Gimzie]

Is the slow (~30 seconds after the track starts) upload time for the covers something on FreeImageHost's side? I assume full-size covers aren't being uploaded at least, but rather smaller copies.

Edit: Some covers take incredibly long to upload, maybe after 15 minutes of the same album being played.

[Bakaba]

For some reason, buttons don't show for me, oh well

[Rings4]

This works perfectly for me. Thanks so much for updating it! It's great to have artwork again, along with the progress bar.