Update installation instructions.

Author: mstange

README.md

@@ -23,13 +23,15 @@ You have the following options to install samply:
 ### Install prebuilt binaries via shell script
 
 macOS/Linux:
+
 ```sh
-curl --proto '=https' --tlsv1.2 -LsSf https://github.com/mstange/samply/releases/download/samply-v0.12.0/samply-installer.sh | sh
+curl --proto '=https' --tlsv1.2 -LsSf https://github.com/mstange/samply/releases/download/samply-v0.13.1/samply-installer.sh | sh
 ```
 
 Windows:
-```
-powershell -c "irm https://github.com/mstange/samply/releases/download/samply-v0.12.0/samply-installer.ps1 | iex"
+
+```sh
+powershell -ExecutionPolicy Bypass -c "irm https://github.com/mstange/samply/releases/download/samply-v0.13.1/samply-installer.ps1 | iex"
 ```
 
 ### Install from crates.io with cargo