Modernize executable names
    
    Rename the Python-versioned executables not to start with "python"
      (if you have python3-mako installed and you type python[tab], it gets in the way)
    
    Make mako-render Python 3 on Fedora 32+
      See https://fedoraproject.org/wiki/Changes/Python_means_Python3
      (arguably, this is correct for F31 as well, but the timing is not good for that)