Progress bar

[aytey]

When VectorCAST/ATG is running, we don't have any view on the progress, apart from when an environment "finishes".

However, as a user watching things, we don't know how many have finished and how many or left -- we should look at building progress monitors here.

A good choice here is probably tqdm. Also, see here: Manual.

We should have progress bars for:

• Building the Manage environments

• Running VectorCAST/ATG ("first pass")

• Generating expected values ("second pass")

Also need to make sure that this works if you pipe the output to a file.