CMake automatic dependencies generation changes

[Orion Poplawski]

For a while now we have generated rpm cmake provides automatically for 
packages that install cmake "packages".  The was done in a 
case-sensitive manner using the name of the cmake files installed.

However, cmake looks for packages in a case-insensitive manner so 
distributions that have also enabled automatic generation of rpm 
requires ran into issues where the provides were one case and the 
requires another.

I have just built cmake-3.17.0-0.2.fc33 with a change from OpenMandriva 
that now produces both the old provides as well as a lower case version 
to allow for a gradual transition.

It also switches the generators to use python 3.

It may also be time to think about enabling automatic requires 
generation as well.  However, I don't have the time to drive this process.

- Orion

-- 
Orion Poplawski
Manager of NWRA Technical Systems          720-772-5637
NWRA, Boulder/CoRA Office             FAX: [phone]
3380 Mitchell Lane                       orion(a)nwra.com
Boulder, CO 80301                 https://www.nwra.com/