Summary:
The installation instructions didn't flow very well.
"Using flipper at Facebook" is now gone. It's installation steps have been moved into the desktop app page, with internal/external switching.
I've also removed the "Updating Flipper" internal page, and put equivalent info in the installation section.
Reviewed By: nikoant
Differential Revision: D25637831
fbshipit-source-id: 2af2abf57793d54804f5c45e3335b8641743e1c8
2f9d4280c1