Change Acts lib install dir, enable MaterialPlugin
This MR adds the cmake flags
-DACTS_BUILD_MATERIAL_PLUGIN:STRING=ON
-DCMAKE_INSTALL_LIBDIR:PATH=lib
to the Acts ExternalProject build, which makes the build output shared libs into lib/
instead of lib64/
and enables the build of the material plugin.
Also, in line with the changes introduced by acts-core!434, the naming of the package is changed to Acts.
Edited by Paul Gessinger