additional options for orbi_define_block_for_flow_injection()

[sebkopf]

we discussed that the following parameters would be useful for defining the data block in flow injenctions (in addition to the time window definitions) by basically providing a way to more automatically detect peak maxima:

intensity_setpoint = 95
intensity_cutoff  = 10

--> this basically selects the peak by taking only everything above 10% of the 95% percentile of the data inside the time window
please correct me if that's wrong @NilsKuhlbusch

note that this is planned for v1.4 at the earliest