3098 - tests on actual sessions
3099 - tangle tests session results

Requires a hacky change to run to skip eval'ing the final empty line.
We want the result, but it's not clear if the current implementation will
last.

Uncovered a broken test in the process.
3100

More consistently use two spaces to separate multiple statements on a line,
and replacement tokens in a #define.
3101
3102 - better support for multi-session scenarios