Allow to "mask out" values intervals in histogram computation
Approximate overview method of statistics computation will get augmented to allow "masking out" of certain values (value intervals) from histogram and its min/max range.
context: quite some products have got multiple "nodata" values, not just one - example being whole Pleiades constellation frequently using 0 + 1 as nodata values. Current histogram computation does not consider 0 (as its set on band as nodata) but considers 1 as valid pixel value, therefore it skews the possible rendering towards 0. Although being a source data problem, this configurable mitigation should not be much work and will improve rendering balance.