plotFakeClosure: chmod +x
move first to utils
drop unused FakeClosurePlot::getFakeSys
utils: rmIfExists
rootUtils: addnl args referenceLine, topRightLegend
SampleUtils: colors
FakeClosurePlot: bug reminder, ask Matt
python rewrite of plotFakeClosure

Details:
- now I understand how the errors and all the other stuff is computed.
  I think there might actually be a small bug in the old implementation.
- 710 -> 295 LOC
- verified that the output is the same
fake.txt: update to new script