docs: use wget/curl & also show source on top

See coop-cloud/organising#591

docs/abra/install.md

@@ -2,14 +2,34 @@
 title: Install
 ---
 
+## Installer script source
+
+You can view that [here](https://git.coopcloud.tech/coop-cloud/abra/src/branch/main/scripts/installer/installer).
+
 ## Stable release
 
+### Wget
+
+```
+wget -q -O - https://install.abra.coopcloud.tech | bash
+```
+
+### Curl
+
 ```
 curl https://install.abra.coopcloud.tech | bash
 ```
 
 ## Release candidate
 
+### Wget
+
+```
+wget -q -O - https://install.abra.coopcloud.tech | bash -s -- --rc
+```
+
+### Curl
+
 ```
 curl https://install.abra.coopcloud.tech | bash -s -- --rc
 ```
@@ -36,10 +56,6 @@ Otherwise, you downloaded a corrupted file and you should re-download it.
 
 Follow the guide [here](https://docs.coopcloud.tech/abra/hack/)
 
-## Installer script source
-
-You can view that [here](https://git.coopcloud.tech/coop-cloud/abra/src/branch/main/scripts/installer/installer).
-
 ## Using Docker
 
 ```