Update Building from Source Docs

[GregoryComer]

📚 The doc issue

Our current building from source docs can use some improvements to be clearer and flow better. Derrick Johnson made the following suggestions, which I would like to make for 1.0.

• Clarify which systems provide prebuilt pip packages and which require building from source.
• Move Windows-specific env setup to near the rest of the env setup info.
• Call out git submodule sync and update/init.
• Move ccache info to the bottom as to not disrupt the main flow.
• Use -S and -B args to cmake invocations instead of changing directory
• Move CMake option descriptions up near where we tell people to do cmake configuration.
• Clean up remaining cases where we're installing into the build directory.

Suggest a potential alternative/fix

No response

cc @mergennachin @byjlw