build sphinx documentation from cmake build, remove docs/Makefile

[edwardhartnett]

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No hand-rolled makefiles please. The sphinx documentation should be build from cmake. @kgerheiser can assist with the cmake commands.

[kgerheiser]

Is there anything I need to do here? What Sphinx documentation are you referring to?

[edwardhartnett]

There is a Makefile in the docs directory that does something to generate spinx documentation from some document files (also in docs).

THis needs to be integrated with the existing documentation build in CMake.