Bugfix: print scenario names correctly when backgrounds exist

Previously, the scenario's name was displayed, then the background steps
were printed, and finally an incorrect scenario name (corresponding to
the first scenario run with that background) was displayed.

With this bugfix, the background is displayed, followed by the correct
scenario name.
Bugfix: scenario name alignment with rfill should ignore tags

When measuring the columnb width, only the last line of the scenario
name should be considered. Otherwise, the line number information is
insufficiently spaced (because it's missing the spacing chars
incorrectly subtracted due to the length of tags, etc. in the lines
Bugfix: scenario name alignment with rfill should ignore tags

When measuring the columnb width, only the last line of the scenario
name should be considered. Otherwise, the line number information is
insufficiently spaced (because it's missing the spacing chars
incorrectly subtracted due to the length of tags, etc. in the lines
above the scenario name.