Add "Extreme' flag to "drop" modules [0,1,....13] in Velo clustering and Velo Tracking

Add an extra flag in ConfigHLT1 dictionary to seed the "drop" of modules [0,1,....13] in Velo clustering and Velo Tracking. This is probably the most extreme configuration we can thing to have so far which can deliver reasonable tracking efficiencies in HLT1.

Of course, that's something to be used carefully in testing and to interpret the results. From a fast test I did with this configuration the HLT1-BestThroughput sequence plus the ExtremeFlag reaches around 24kEvt/s/node.

I decided to plug this extra flag to confirm what i was saying during the USPG meeting that removing the modules in decoding and tracking was already implemented ( by @tlatham some time ago) but we never really considered seriously that approach. Since now it seems like we are comparing things with solutions where part of the velo could not be used for tracking, this MR is something needed.

FYI: @adudziak , @gligorov , @fpolci , @gdujany , @chasse , @graven .

@gtuci can you have a look if the modules I drop are the same you are decoding and doing tracking with for the Retina algorithm?