Add mention of the Windows Package Manager
Add mention of the Windows Package Manager

Update the installation guide to mention winget, the Windows Package Manager.

Minikube is in the repository, and the command I listed works correctly:
andre@IRIDIUM-MMXX  C:\Windows\System32                                                                      [16:11]
❯ winget search minikube
Name     Id                  Version
------------------------------------
minikube Kubernetes.minikube 1.15.1
andre@IRIDIUM-MMXX  C:\Windows\System32                                                                      [16:12]
❯ winget install minikube
Found minikube [Kubernetes.minikube]
This application is licensed to you by its owner.
Microsoft is not responsible for, nor does it grant any licences to, third-party packages.
Downloading https://storage.googleapis.com/minikube/releases/latest/minikube-installer.exe
  ██████████████████████████████  23.7 MB / 23.7 MB
Successfully verified installer hash
Starting package install...
Successfully installed
warmchang/minikube,kubernetes/minikube,kubernetes/minikube,kubernetes/minikube,warmchang/minikube,kubernetes/minikube,kubernetes/minikube,warmchang/minikube,warmchang/minikube,kubernetes/minikube,warmchang/minikube,warmchang/minikube,warmchang/minikube,kubernetes/minikube