Internal test tools are now separated into two classes, common tools are
symlinked to tests/bin and are on PATH, remaining tools are invoked with
full path.
The README file had some stale TODO entries that were changed earlier,
those are now marked as done.
Lastly any-python is now on PATH, so that scripts can invoke it via #!
mechanism.
Signed-off-by: Zygmunt Krynicki <me@zygoon.pl>
