update and improve emulator

emulator/third-party/love/readme.txt

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+LÖVE is an *awesome* framework you can use to make 2D games in Lua. It's free, open-source, and works on Windows, macOS, Linux, Android, and iOS.
+
+[![Build Status: Windows](https://ci.appveyor.com/api/projects/status/chc0hdr08wv1d5c7?svg=true)](https://ci.appveyor.com/project/slime73/love)
+[![Build Status: Github CI](https://github.com/love2d/love/workflows/continuous-integration/badge.svg)](https://github.com/love2d/love/actions?query=workflow%3Acontinuous-integration)
+
+Documentation
+-------------
+
+We use our [wiki][wiki] for documentation.
+If you need further help, feel free to ask on our [forums][forums], our [Discord server][discord], or our [subreddit][subreddit].
+
+Repository
+----------
+
+We use the 'main' branch for patch development of the current major release, and therefore it should not be considered stable.
+There may also be a branch for the next major version in development, which is named after that version.
+
+We tag all our releases (since we started using mercurial and git), and have binary downloads available for them.
+
+Experimental changes are developed in a separate [love-experiments][love-experiments] repository.
+
+Builds
+------
+
+Files for releases are in the [releases][releases] section on GitHub. [The site][site] has links to files and additional platform content for the latest release.
+
+There are also unstable/nightly builds:
+
+- Builds for some platforms are automatically created after each commit and are available through GitHub's CI interfaces.
+- For ubuntu linux they are in [ppa:bartbes/love-unstable][unstableppa]
+- For arch linux there's [love-git][aur] in the AUR.
+
+Contributing
+------------
+
+The best places to contribute are through the issue tracker and the official Discord server or IRC channel.
+
+For code contributions, pull requests and patches are welcome. Be sure to read the [source code style guide][codestyle].
+Changes and new features typically get discussed in the issue tracker or on Discord or the forums before a pull request is made.
+
+Compilation
+-----------
+
+### Windows
+Follow the instructions at the [megasource][megasource] repository page.
+
+### *nix
+Run `platform/unix/automagic` from the repository root, then run ./configure and make.
+
+	$ platform/unix/automagic
+	$ ./configure
+	$ make
+
+When using a source release, automagic has already been run, and the first step can be skipped.
+
+### macOS
+Download or clone [this repository][dependencies-apple] and copy, move, or symlink the `macOS/Frameworks` subfolder into love's `platform/xcode/macosx` folder.
+
+Then use the Xcode project found at `platform/xcode/love.xcodeproj` to build the `love-macosx` target.
+
+### iOS
+Building for iOS requires macOS and Xcode.
+
+#### LÖVE 11.4 and newer
+Download the `love-apple-dependencies` zip file corresponding to the LÖVE version being used from the [Releases page][dependencies-ios],
+unzip it, and place the `iOS/libraries` subfolder into love's `platform/xcode/ios` folder.
+
+Or, download or clone [this repository][dependencies-apple] and copy, move, or symlink the `iOS/libraries` subfolder into love's `platform/xcode/ios` folder.
+
+Then use the Xcode project found at `platform/xcode/love.xcodeproj` to build the `love-ios` target.
+
+See `readme-iOS.rtf` for more information.
+
+#### LÖVE 11.3 and older
+Download the `ios-libraries` zip file corresponding to the LÖVE version being used from the [Releases page][dependencies-ios],
+unzip it, and place the `include` and `libraries` subfolders into love's `platform/xcode/ios` folder.
+
+Then use the Xcode project found at `platform/xcode/love.xcodeproj` to build the `love-ios` target.
+
+See `readme-iOS.rtf` for more information.
+
+### Android
+Visit the [Android build repository][android-repository] for build instructions.
+
+Dependencies
+------------
+
+- SDL2
+- OpenGL 2.1+ / OpenGL ES 2+
+- OpenAL
+- Lua / LuaJIT / LLVM-lua
+- FreeType
+- ModPlug
+- mpg123
+- Vorbisfile
+- Theora
+
+[site]: https://love2d.org
+[wiki]: https://love2d.org/wiki
+[forums]: https://love2d.org/forums
+[discord]: https://discord.gg/rhUets9
+[subreddit]: https://www.reddit.com/r/love2d
+[dependencies-apple]: https://github.com/love2d/love-apple-dependencies
+[dependencies-ios]: https://github.com/love2d/love/releases
+[megasource]: https://github.com/love2d/megasource
+[unstableppa]: https://launchpad.net/~bartbes/+archive/love-unstable
+[aur]: https://aur.archlinux.org/packages/love-git
+[love-experiments]: https://github.com/slime73/love-experiments
+[codestyle]: https://love2d.org/wiki/Code_Style
+[android-repository]: https://github.com/love2d/love-android
+[releases]: https://github.com/love2d/love/releases