validation/aggregating/pipeline/aggregating_validations_pipeline.odg: diff tables: integrated row labels into table

validation/aggregating/pipeline/aggregating_validations_pipeline.odg: diff tables: added line for different rows (vs. missing/extra)

validation/aggregating/pipeline/aggregating_validations_pipeline.odg: show that the staging table(s) are denormalized before running the input queries on them. clarified that what is compared are the input and output query results, not the queries themselves.

validation/aggregating/pipeline/aggregating_validations_pipeline.odg: made "diff tables" the same size as the other major labels

validation/aggregating/pipeline/aggregating_validations_pipeline.odg: added CSVs export arrows and import process arrows, as decided in conference call

added validation/aggregating/pipeline/aggregating_validations_pipeline.odg with .png export