Link to additional installation instructions from Quickstart (#4645)
Link to additional installation instructions from Quickstart (#4645)

* Add Windows command prompt install instructions

* Link out to additional methods

Since there are multiple additional installation methods, it doesn't
make sense to privilege one of them by inlining it here. Instead, we
will link out to the additional methods per OS.

* Give examples of alternative installations inline

* Improve link labels
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