betterdiscordctl: add page (#8166)

pages/linux/betterdiscordctl.md

@@ -0,0 +1,24 @@
+# betterdiscordctl
+
+> A program for managing BetterDiscord on Linux.
+> More information: <https://github.com/bb010g/betterdiscordctl#manual>.
+
+- Install BetterDiscord on Discord Stable:
+
+`sudo betterdiscordctl install`
+
+- Install BetterDiscord on Discord Canary:
+
+`sudo betterdiscordctl --d-flavors canary install`
+
+- Install BetterDiscord on Discord PTB:
+
+`sudo betterdiscordctl --d-flavors ptb install`
+
+- Install BetterDiscord on Discord installed with Flatpak:
+
+`sudo betterdiscordctl --d-install flatpak install`
+
+- Install BetterDiscord on Discord installed with Snap:
+
+`sudo betterdiscordctl --d-install snap install`