- Fix build for Leap 15.3

- Compile with %optflags

- Add reproducible.patch to drop build date (boo#1047218)

- Update to version 8.245:
* Significant speedup of parton distribution handling.
* Several fixes to avoid out-of-bound evaluation of vectors in
the merging code.
* Several fixes to correctly handle CKKW-L merging of EWkino-
and higgsino-processes have been included.
* Include the functionality for MC@NLO-Delta matching with
aMC@NLO.
* Further bug fixes for the hard process name handling for
weak-boson-fusion-like processes, that led to an incorrect
counting of additional emissions.
* Small fixes to history construction in the presence of
multiple resonances.
* The primordial kT for LHE files is now set by the
BeamRemnants:primordialKThard average value, rather than the
LHE scale, since the latter may be quite low e.g. in the
POWHEG approach.
* The problem of "dangling" gluons causing changing color flows
in SimpleTimeShower for top decays is now fixed.
* Extra check added to SimpleSpaceShower for the case where a
small daughter PDF value can lead to an infinite loop if PDF
variations are switched on.
* Bug fixed in the new possibility to let particles with narrow
widths (such as onia states) obtain a simple Breit-Wigner