Complete rewrite of the custom account implementation to add support for using any Yggdrasil-compatible API server by @evan-goode in #112.
Fixed incorrect messages about having to add an account that owns Minecraft before you can play.
Fixed Polly the Parrot background not showing up on halloween.
Pulled changes from Prism 8.0 (Done by @evan-goode in #116).
One of the changes made in Prism 8.0 was the removal of windows-legacy builds.
The main difference between regular and legacy builds is the regular builds require Windows 10 while the legacy builds required Windows 7.
I'm very sorry if you're on an older Windows version and unable to use the launcher due to this.
I initially wanted to revert this change but after learning they dropped support because Qt stopped including OpenSSL 1.1 binaries for Windows and the replacement OpenSSL 3 binaries are only included with Qt6 which only supports Windows 10 or newer I realised re-adding the legacy builds would be more hassle than it's worth, sorry.
