LinkDef: drop enums

These were added when I was trying to access the enums from python.
Then I decided to go another path (see `utils.import_SUSYDefs_enums`),
so they are now obsolete. In fact, they are wrong (not matching the
current namespace); I don't understand how come cint didn't complain.
fix utils.import_SUSYDefs_enums

This broke with dab28b9 where the systematic enum was moved from
`SusyDef.h` to `SusyNtSys.h`. Now fixed by refactoring the function
and allowing to pick up different enums from different header files.
plot_comparison.py: also print run/event and jets

Re-use this script to make the event-by-event comparison.
Tested with the two files (from xaod and from nutpsuys) made with the
100 events from run 204442. Now going to debug its output.
Merge pull request #42 from gerbaudo/xaod-event-comparison

Xaod event comparison