Doesn't differ from main.cpp much and it is in history, anyways.
This change is mostly to allow batch removal of .orig files in repo
without affecting a tracked file.
This reduces sources size by a great deal - matrices occupied some
33 MBs.
Seems useless - matrices are should be perhaps reconstructed by
matrix-gen but seem incompatible with current version (doesn't
have k/m/c header).
The scripts are not compatible with current version (and used data/
is missing).