- oldhepdata parser: don't prepend 'Data from' to blank location or append '.' to blank description.
- csv writer: always write directory for whole submission even if there is only one table.
- root and yoda writers: don't assume bin focus is at bin midpoint for independent variables.
- csv writer: always write the bin focus for independent variables in addition to the bin edges.
- root writer: don't write a TGraph2DErrors object if any of the variables have asymmetric errors.
- yoda writer: don't default to writing a Scatter2D object for more than two independent variables.
- yoda writer: write plus/minus asymmetric errors instead of just a plus-only symmetric error.
- testdata: update to accommodate above changes so tests pass.