This reworks the OSX bundle script, to run it easily on CI and to
further also build the unix tarballs and the windows installer.
Clean up the MacOS bundle detection, by not forcing a compilation-time
switch.
Clean up shared library compilation: changing the installation name
isn't necessary for 0 A.D.
Differential Revision: https://code.wildfiregames.com/D3161
This was SVN commit r24343.
wraitii
d95550248b