Powershell for GitHub setup
I got an answer from GitHub support:
The enhanced prompt is provided by posh-git [1], and it isn't added when you run the line in shell.ps1. However, it's easy enough to install.
Just cd to C:\Users\Username\AppData\GitHub\PoshGit_* and run the install.ps1 script from PowerShell. It will add it to your PowerShell $profile automatically.