migration guide: rename linux to unix, add more information to windows

Signed-off-by: Exverge <exverge@exverge.xyz>

MIGRATION.md

@@ -0,0 +1,21 @@
+# Migrating from yuzu
+
+When coming from yuzu, the migration is as easy as renaming some directories.
+
+## Windows
+
+Use the run dialog to go to `%APPDATA%` or manually go to `C:\Users\{USERNAME}\AppData\Roaming` (you may have to enable hidden files) and simply rename the `yuzu` directories and simply rename those to `suyu`.
+
+## Unix (macOS/Linux)
+Similarly, you can simply rename the folders `~/.local/share/yuzu` and `~/.config/yuzu` to `suyu`, either via a file manager or with the following commands:
+```sh
+ $ mv ~/.local/share/yuzu ~/.local/share/suyu
+ $ mv ~/.config/yuzu ~/.config/suyu
+```
+There is also `~/.cache/yuzu`, which you can safely delete. Suyu will build a fresh cache in its own directory.
+
+### Linux
+Depending on your setup, you may want to substitute those base paths for `$XDG_DATA_HOME` and `$XDG_CONFIG_HOME` respectively.
+
+## Android
+TBD

README.md

@@ -41,6 +41,10 @@ It is written in C++ (C# possibly required soon) with portability in mind, we ac
 ## Hardware Requirements
 [Click here to see the Hardware Requirements](https://git.suyu.dev/suyu/suyu/wiki/Hardware-Requirements)
 
+## Migrating from yuzu
+
+See [MIGRATION.md](MIGRATION.md).
+
 ## Status
 
 We currently have builds over at the [Releases](https://git.suyu.dev/suyu/suyu/releases) page.