Put installed_files.txt in `$(pyexecdir)/opendiamond`
Put installed_files.txt in `$(pyexecdir)/opendiamond`

This is different from `$(pkgpythondir)` on RHEL.

cmusatyalab/opendiamond,cmusatyalab/opendiamond,cmusatyalab/opendiamond,cmusatyalab/opendiamond,cmusatyalab/opendiamond